MDL-75481 lib: Updated MongoDB files to 1.13.1

cache/stores/mongodb/MongoDB/BulkWriteResult.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,

cache/stores/mongodb/MongoDB/ChangeStream.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2017 MongoDB, Inc.
+ * Copyright 2017-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -24,6 +24,8 @@ use MongoDB\Driver\Exception\RuntimeException;
 use MongoDB\Driver\Exception\ServerException;
 use MongoDB\Exception\ResumeTokenException;
 use MongoDB\Model\ChangeStreamIterator;
+use ReturnTypeWillChange;
+
 use function call_user_func;
 use function in_array;
 
@@ -32,7 +34,7 @@ use function in_array;
  *
  * @api
  * @see \MongoDB\Collection::watch()
- * @see http://docs.mongodb.org/manual/reference/command/changeStream/
+ * @see https://mongodb.com/docs/manual/reference/method/db.watch/#mongodb-method-db.watch
  */
 class ChangeStream implements Iterator
 {
@@ -40,7 +42,7 @@ class ChangeStream implements Iterator
      * @deprecated 1.4
      * @todo Remove this in 2.0 (see: PHPLIB-360)
      */
-    const CURSOR_NOT_FOUND = 43;
+    public const CURSOR_NOT_FOUND = 43;
 
     /** @var int */
     private static $cursorNotFound = 43;
@@ -54,11 +56,11 @@ class ChangeStream implements Iterator
         189, // PrimarySteppedDown
         262, // ExceededTimeLimit
         9001, // SocketException
-        10107, // NotMaster
+        10107, // NotPrimary
         11600, // InterruptedAtShutdown
         11602, // InterruptedDueToReplStateChange
-        13435, // NotMasterNoSlaveOk
-        13436, // NotMasterOrSecondary
+        13435, // NotPrimaryNoSecondaryOk
+        13436, // NotPrimaryOrSecondary
         63, // StaleShardVersion
         150, // StaleEpoch
         13388, // StaleConfig
@@ -98,9 +100,10 @@ class ChangeStream implements Iterator
     }
 
     /**
-     * @see http://php.net/iterator.current
+     * @see https://php.net/iterator.current
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function current()
     {
         return $this->iterator->current();
@@ -129,9 +132,10 @@ class ChangeStream implements Iterator
     }
 
     /**
-     * @see http://php.net/iterator.key
+     * @see https://php.net/iterator.key
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function key()
     {
         if ($this->valid()) {
@@ -142,10 +146,11 @@ class ChangeStream implements Iterator
     }
 
     /**
-     * @see http://php.net/iterator.next
+     * @see https://php.net/iterator.next
      * @return void
      * @throws ResumeTokenException
      */
+    #[ReturnTypeWillChange]
     public function next()
     {
         try {
@@ -157,10 +162,11 @@ class ChangeStream implements Iterator
     }
 
     /**
-     * @see http://php.net/iterator.rewind
+     * @see https://php.net/iterator.rewind
      * @return void
      * @throws ResumeTokenException
      */
+    #[ReturnTypeWillChange]
     public function rewind()
     {
         try {
@@ -175,9 +181,10 @@ class ChangeStream implements Iterator
     }
 
     /**
-     * @see http://php.net/iterator.valid
+     * @see https://php.net/iterator.valid
      * @return boolean
      */
+    #[ReturnTypeWillChange]
     public function valid()
     {
         return $this->iterator->valid();

cache/stores/mongodb/MongoDB/Client.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -38,6 +38,7 @@ use MongoDB\Operation\ListDatabaseNames;
 use MongoDB\Operation\ListDatabases;
 use MongoDB\Operation\Watch;
 use Throwable;
+
 use function is_array;
 use function is_string;
 
@@ -50,12 +51,6 @@ class Client
         'root' => BSONDocument::class,
     ];
 
-    /** @var integer */
-    private static $wireVersionForReadConcern = 4;
-
-    /** @var integer */
-    private static $wireVersionForWritableCommandWriteConcern = 5;
-
     /** @var string */
     private static $handshakeSeparator = ' / ';
 
@@ -93,9 +88,9 @@ class Client
      *
      * Other options are documented in MongoDB\Driver\Manager::__construct().
      *
-     * @see http://docs.mongodb.org/manual/reference/connection-string/
-     * @see http://php.net/manual/en/mongodb-driver-manager.construct.php
-     * @see http://php.net/manual/en/mongodb.persistence.php#mongodb.persistence.typemaps
+     * @see https://mongodb.com/docs/manual/reference/connection-string/
+     * @see https://php.net/manual/en/mongodb-driver-manager.construct.php
+     * @see https://php.net/manual/en/mongodb.persistence.php#mongodb.persistence.typemaps
      * @param string $uri           MongoDB connection string
      * @param array  $uriOptions    Additional connection string options
      * @param array  $driverOptions Driver-specific options
@@ -135,7 +130,7 @@ class Client
     /**
      * Return internal properties for debugging purposes.
      *
-     * @see http://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
+     * @see https://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
      * @return array
      */
     public function __debugInfo()
@@ -155,8 +150,8 @@ class Client
      * be selected with complex syntax (e.g. $client->{"that-database"}) or
      * {@link selectDatabase()}.
      *
-     * @see http://php.net/oop5.overloading#object.get
-     * @see http://php.net/types.string#language.types.string.parsing.complex
+     * @see https://php.net/oop5.overloading#object.get
+     * @see https://php.net/types.string#language.types.string.parsing.complex
      * @param string $databaseName Name of the database to select
      * @return Database
      */
@@ -214,7 +209,7 @@ class Client
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -236,7 +231,7 @@ class Client
     /**
      * Return the read concern for this client.
      *
-     * @see http://php.net/manual/en/mongodb-driver-readconcern.isdefault.php
+     * @see https://php.net/manual/en/mongodb-driver-readconcern.isdefault.php
      * @return ReadConcern
      */
     public function getReadConcern()
@@ -267,7 +262,7 @@ class Client
     /**
      * Return the write concern for this client.
      *
-     * @see http://php.net/manual/en/mongodb-driver-writeconcern.isdefault.php
+     * @see https://php.net/manual/en/mongodb-driver-writeconcern.isdefault.php
      * @return WriteConcern
      */
     public function getWriteConcern()
@@ -283,7 +278,7 @@ class Client
      * @throws InvalidArgumentException for parameter/option parsing errors
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
-    public function listDatabaseNames(array $options = []) : Iterator
+    public function listDatabaseNames(array $options = []): Iterator
     {
         $operation = new ListDatabaseNames($options);
         $server = select_server($this->manager, $options);
@@ -345,7 +340,7 @@ class Client
     /**
      * Start a new client session.
      *
-     * @see http://php.net/manual/en/mongodb-driver-manager.startsession.php
+     * @see https://php.net/manual/en/mongodb-driver-manager.startsession.php
      * @param array $options Session options
      * @return Session
      */
@@ -371,7 +366,7 @@ class Client
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['readConcern']) && server_supports_feature($server, self::$wireVersionForReadConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['readConcern']) && ! is_in_transaction($options)) {
             $options['readConcern'] = $this->readConcern;
         }
 
@@ -384,7 +379,7 @@ class Client
         return $operation->execute($server);
     }
 
-    private static function getVersion() : string
+    private static function getVersion(): string
     {
         if (self::$version === null) {
             try {
@@ -397,7 +392,7 @@ class Client
         return self::$version;
     }
 
-    private function mergeDriverInfo(array $driver) : array
+    private function mergeDriverInfo(array $driver): array
     {
         $mergedDriver = [
             'name' => 'PHPLIB',

cache/stores/mongodb/MongoDB/Collection.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -53,11 +53,13 @@ use MongoDB\Operation\InsertMany;
 use MongoDB\Operation\InsertOne;
 use MongoDB\Operation\ListIndexes;
 use MongoDB\Operation\MapReduce;
+use MongoDB\Operation\RenameCollection;
 use MongoDB\Operation\ReplaceOne;
 use MongoDB\Operation\UpdateMany;
 use MongoDB\Operation\UpdateOne;
 use MongoDB\Operation\Watch;
 use Traversable;
+
 use function array_diff_key;
 use function array_intersect_key;
 use function current;
@@ -73,15 +75,6 @@ class Collection
         'root' => BSONDocument::class,
     ];
 
-    /** @var integer */
-    private static $wireVersionForFindAndModifyWriteConcern = 4;
-
-    /** @var integer */
-    private static $wireVersionForReadConcern = 4;
-
-    /** @var integer */
-    private static $wireVersionForWritableCommandWriteConcern = 5;
-
     /** @var integer */
     private static $wireVersionForReadConcernWithWriteStage = 8;
 
@@ -135,11 +128,11 @@ class Collection
      */
     public function __construct(Manager $manager, $databaseName, $collectionName, array $options = [])
     {
-        if (strlen($databaseName) < 1) {
+        if (strlen((string) $databaseName) < 1) {
             throw new InvalidArgumentException('$databaseName is invalid: ' . $databaseName);
         }
 
-        if (strlen($collectionName) < 1) {
+        if (strlen((string) $collectionName) < 1) {
             throw new InvalidArgumentException('$collectionName is invalid: ' . $collectionName);
         }
 
@@ -171,7 +164,7 @@ class Collection
     /**
      * Return internal properties for debugging purposes.
      *
-     * @see http://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
+     * @see https://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
      * @return array
      */
     public function __debugInfo()
@@ -190,7 +183,7 @@ class Collection
     /**
      * Return the collection namespace (e.g. "db.collection").
      *
-     * @see https://docs.mongodb.org/manual/faq/developers/#faq-dev-namespace
+     * @see https://mongodb.com/docs/manual/core/databases-and-collections/
      * @return string
      */
     public function __toString()
@@ -223,19 +216,17 @@ class Collection
             $options['readPreference'] = $this->readPreference;
         }
 
-        if ($hasWriteStage) {
-            $options['readPreference'] = new ReadPreference(ReadPreference::RP_PRIMARY);
-        }
-
-        $server = select_server($this->manager, $options);
+        $server = $hasWriteStage
+            ? select_server_for_aggregate_write_stage($this->manager, $options)
+            : select_server($this->manager, $options);
 
         /* MongoDB 4.2 and later supports a read concern when an $out stage is
          * being used, but earlier versions do not.
          *
          * A read concern is also not compatible with transactions.
          */
-        if (! isset($options['readConcern']) &&
-            server_supports_feature($server, self::$wireVersionForReadConcern) &&
+        if (
+            ! isset($options['readConcern']) &&
             ! is_in_transaction($options) &&
             ( ! $hasWriteStage || server_supports_feature($server, self::$wireVersionForReadConcernWithWriteStage))
         ) {
@@ -246,10 +237,7 @@ class Collection
             $options['typeMap'] = $this->typeMap;
         }
 
-        if ($hasWriteStage &&
-            ! isset($options['writeConcern']) &&
-            server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) &&
-            ! is_in_transaction($options)) {
+        if ($hasWriteStage && ! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -303,7 +291,7 @@ class Collection
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['readConcern']) && server_supports_feature($server, self::$wireVersionForReadConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['readConcern']) && ! is_in_transaction($options)) {
             $options['readConcern'] = $this->readConcern;
         }
 
@@ -332,7 +320,7 @@ class Collection
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['readConcern']) && server_supports_feature($server, self::$wireVersionForReadConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['readConcern']) && ! is_in_transaction($options)) {
             $options['readConcern'] = $this->readConcern;
         }
 
@@ -380,8 +368,8 @@ class Collection
      * If the "name" option is unspecified, a name will be generated from the
      * "key" document.
      *
-     * @see http://docs.mongodb.org/manual/reference/command/createIndexes/
-     * @see http://docs.mongodb.org/manual/reference/method/db.collection.createIndex/
+     * @see https://mongodb.com/docs/manual/reference/command/createIndexes/
+     * @see https://mongodb.com/docs/manual/reference/method/db.collection.createIndex/
      * @see CreateIndexes::__construct() for supported command options
      * @param array[] $indexes List of index specifications
      * @param array   $options Command options
@@ -394,7 +382,7 @@ class Collection
     {
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -407,7 +395,7 @@ class Collection
      * Deletes all documents matching the filter.
      *
      * @see DeleteMany::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/delete/
+     * @see https://mongodb.com/docs/manual/reference/command/delete/
      * @param array|object $filter  Query by which to delete documents
      * @param array        $options Command options
      * @return DeleteResult
@@ -431,7 +419,7 @@ class Collection
      * Deletes at most one document matching the filter.
      *
      * @see DeleteOne::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/delete/
+     * @see https://mongodb.com/docs/manual/reference/command/delete/
      * @param array|object $filter  Query by which to delete documents
      * @param array        $options Command options
      * @return DeleteResult
@@ -476,7 +464,7 @@ class Collection
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['readConcern']) && server_supports_feature($server, self::$wireVersionForReadConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['readConcern']) && ! is_in_transaction($options)) {
             $options['readConcern'] = $this->readConcern;
         }
 
@@ -503,10 +491,25 @@ class Collection
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
+        $encryptedFields = $options['encryptedFields']
+            ?? get_encrypted_fields_from_driver($this->databaseName, $this->collectionName, $this->manager)
+            ?? get_encrypted_fields_from_server($this->databaseName, $this->collectionName, $this->manager, $server)
+            ?? null;
+
+        if ($encryptedFields !== null) {
+            // encryptedFields is not passed to the drop command
+            unset($options['encryptedFields']);
+
+            $encryptedFields = (array) $encryptedFields;
+            (new DropCollection($this->databaseName, $encryptedFields['escCollection'] ?? 'enxcol_.' . $this->collectionName . '.esc'))->execute($server);
+            (new DropCollection($this->databaseName, $encryptedFields['eccCollection'] ?? 'enxcol_.' . $this->collectionName . '.ecc'))->execute($server);
+            (new DropCollection($this->databaseName, $encryptedFields['ecocCollection'] ?? 'enxcol_.' . $this->collectionName . '.ecoc'))->execute($server);
+        }
+
         $operation = new DropCollection($this->databaseName, $this->collectionName, $options);
 
         return $operation->execute($server);
@@ -537,7 +540,7 @@ class Collection
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -564,7 +567,7 @@ class Collection
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -592,7 +595,7 @@ class Collection
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['readConcern']) && server_supports_feature($server, self::$wireVersionForReadConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['readConcern']) && ! is_in_transaction($options)) {
             $options['readConcern'] = $this->readConcern;
         }
 
@@ -605,7 +608,7 @@ class Collection
      * Explains explainable commands.
      *
      * @see Explain::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/explain/
+     * @see https://mongodb.com/docs/manual/reference/command/explain/
      * @param Explainable $explainable Command on which to run explain
      * @param array       $options     Additional options
      * @return array|object
@@ -634,7 +637,7 @@ class Collection
      * Finds documents matching the query.
      *
      * @see Find::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/core/read-operations-introduction/
+     * @see https://mongodb.com/docs/manual/crud/#read-operations
      * @param array|object $filter  Query by which to filter documents
      * @param array        $options Additional options
      * @return Cursor
@@ -650,7 +653,7 @@ class Collection
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['readConcern']) && server_supports_feature($server, self::$wireVersionForReadConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['readConcern']) && ! is_in_transaction($options)) {
             $options['readConcern'] = $this->readConcern;
         }
 
@@ -667,7 +670,7 @@ class Collection
      * Finds a single document matching the query.
      *
      * @see FindOne::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/core/read-operations-introduction/
+     * @see https://mongodb.com/docs/manual/crud/#read-operations
      * @param array|object $filter  Query by which to filter documents
      * @param array        $options Additional options
      * @return array|object|null
@@ -683,7 +686,7 @@ class Collection
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['readConcern']) && server_supports_feature($server, self::$wireVersionForReadConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['readConcern']) && ! is_in_transaction($options)) {
             $options['readConcern'] = $this->readConcern;
         }
 
@@ -702,7 +705,7 @@ class Collection
      * The document to return may be null if no document matched the filter.
      *
      * @see FindOneAndDelete::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/findAndModify/
+     * @see https://mongodb.com/docs/manual/reference/command/findAndModify/
      * @param array|object $filter  Query by which to filter documents
      * @param array        $options Command options
      * @return array|object|null
@@ -715,7 +718,7 @@ class Collection
     {
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForFindAndModifyWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -738,7 +741,7 @@ class Collection
      * to return the updated document.
      *
      * @see FindOneAndReplace::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/findAndModify/
+     * @see https://mongodb.com/docs/manual/reference/command/findAndModify/
      * @param array|object $filter      Query by which to filter documents
      * @param array|object $replacement Replacement document
      * @param array        $options     Command options
@@ -752,7 +755,7 @@ class Collection
     {
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForFindAndModifyWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -775,7 +778,7 @@ class Collection
      * to return the updated document.
      *
      * @see FindOneAndReplace::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/findAndModify/
+     * @see https://mongodb.com/docs/manual/reference/command/findAndModify/
      * @param array|object $filter  Query by which to filter documents
      * @param array|object $update  Update to apply to the matched document
      * @param array        $options Command options
@@ -789,7 +792,7 @@ class Collection
     {
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForFindAndModifyWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -835,7 +838,7 @@ class Collection
     /**
      * Return the collection namespace.
      *
-     * @see https://docs.mongodb.org/manual/reference/glossary/#term-namespace
+     * @see https://mongodb.com/docs/manual/reference/glossary/#term-namespace
      * @return string
      */
     public function getNamespace()
@@ -846,7 +849,7 @@ class Collection
     /**
      * Return the read concern for this collection.
      *
-     * @see http://php.net/manual/en/mongodb-driver-readconcern.isdefault.php
+     * @see https://php.net/manual/en/mongodb-driver-readconcern.isdefault.php
      * @return ReadConcern
      */
     public function getReadConcern()
@@ -877,7 +880,7 @@ class Collection
     /**
      * Return the write concern for this collection.
      *
-     * @see http://php.net/manual/en/mongodb-driver-writeconcern.isdefault.php
+     * @see https://php.net/manual/en/mongodb-driver-writeconcern.isdefault.php
      * @return WriteConcern
      */
     public function getWriteConcern()
@@ -889,7 +892,7 @@ class Collection
      * Inserts multiple documents.
      *
      * @see InsertMany::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/insert/
+     * @see https://mongodb.com/docs/manual/reference/command/insert/
      * @param array[]|object[] $documents The documents to insert
      * @param array            $options   Command options
      * @return InsertManyResult
@@ -912,7 +915,7 @@ class Collection
      * Inserts one document.
      *
      * @see InsertOne::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/insert/
+     * @see https://mongodb.com/docs/manual/reference/command/insert/
      * @param array|object $document The document to insert
      * @param array        $options  Command options
      * @return InsertOneResult
@@ -952,7 +955,7 @@ class Collection
      * Executes a map-reduce aggregation on the collection.
      *
      * @see MapReduce::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/mapReduce/
+     * @see https://mongodb.com/docs/manual/reference/command/mapReduce/
      * @param JavascriptInterface $map     Map function
      * @param JavascriptInterface $reduce  Reduce function
      * @param string|array|object $out     Output specification
@@ -983,7 +986,7 @@ class Collection
          *
          * A read concern is also not compatible with transactions.
          */
-        if (! isset($options['readConcern']) && ! ($hasOutputCollection && $this->readConcern->getLevel() === ReadConcern::MAJORITY) && server_supports_feature($server, self::$wireVersionForReadConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['readConcern']) && ! ($hasOutputCollection && $this->readConcern->getLevel() === ReadConcern::MAJORITY) && ! is_in_transaction($options)) {
             $options['readConcern'] = $this->readConcern;
         }
 
@@ -991,7 +994,7 @@ class Collection
             $options['typeMap'] = $this->typeMap;
         }
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -1000,11 +1003,44 @@ class Collection
         return $operation->execute($server);
     }
 
+    /**
+     * Renames the collection.
+     *
+     * @see RenameCollection::__construct() for supported options
+     * @param string  $toCollectionName New name of the collection
+     * @param ?string $toDatabaseName   New database name of the collection. Defaults to the original database.
+     * @param array   $options          Additional options
+     * @return array|object Command result document
+     * @throws UnsupportedException if options are not supported by the selected server
+     * @throws InvalidArgumentException for parameter/option parsing errors
+     * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
+     */
+    public function rename(string $toCollectionName, ?string $toDatabaseName = null, array $options = [])
+    {
+        if (! isset($toDatabaseName)) {
+            $toDatabaseName = $this->databaseName;
+        }
+
+        if (! isset($options['typeMap'])) {
+            $options['typeMap'] = $this->typeMap;
+        }
+
+        $server = select_server($this->manager, $options);
+
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
+            $options['writeConcern'] = $this->writeConcern;
+        }
+
+        $operation = new RenameCollection($this->databaseName, $this->collectionName, $toDatabaseName, $toCollectionName, $options);
+
+        return $operation->execute($server);
+    }
+
     /**
      * Replaces at most one document matching the filter.
      *
      * @see ReplaceOne::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/update/
+     * @see https://mongodb.com/docs/manual/reference/command/update/
      * @param array|object $filter      Query by which to filter documents
      * @param array|object $replacement Replacement document
      * @param array        $options     Command options
@@ -1029,7 +1065,7 @@ class Collection
      * Updates all documents matching the filter.
      *
      * @see UpdateMany::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/update/
+     * @see https://mongodb.com/docs/manual/reference/command/update/
      * @param array|object $filter  Query by which to filter documents
      * @param array|object $update  Update to apply to the matched documents
      * @param array        $options Command options
@@ -1054,7 +1090,7 @@ class Collection
      * Updates at most one document matching the filter.
      *
      * @see UpdateOne::__construct() for supported options
-     * @see http://docs.mongodb.org/manual/reference/command/update/
+     * @see https://mongodb.com/docs/manual/reference/command/update/
      * @param array|object $filter  Query by which to filter documents
      * @param array|object $update  Update to apply to the matched document
      * @param array        $options Command options
@@ -1099,7 +1135,7 @@ class Collection
          * related to change streams being unsupported instead of an
          * UnsupportedException regarding use of the "readConcern" option from
          * the Aggregate operation class. */
-        if (! isset($options['readConcern']) && server_supports_feature($server, self::$wireVersionForReadConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['readConcern']) && ! is_in_transaction($options)) {
             $options['readConcern'] = $this->readConcern;
         }
 

cache/stores/mongodb/MongoDB/Command/ListCollections.php

@@ -6,7 +6,7 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -24,6 +24,7 @@ use MongoDB\Driver\Session;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Model\CachingIterator;
 use MongoDB\Operation\Executable;
+
 use function is_array;
 use function is_bool;
 use function is_integer;
@@ -33,7 +34,7 @@ use function is_object;
  * Wrapper for the listCollections command.
  *
  * @internal
- * @see http://docs.mongodb.org/manual/reference/command/listCollections/
+ * @see https://mongodb.com/docs/manual/reference/command/listCollections/
  */
 class ListCollections implements Executable
 {
@@ -48,6 +49,15 @@ class ListCollections implements Executable
      *
      * Supported options:
      *
+     *  * authorizedCollections (boolean): Determines which collections are
+     *    returned based on the user privileges.
+     *
+     *    For servers < 4.0, this option is ignored.
+     *
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
+     *
      *  * filter (document): Query by which to filter collections.
      *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
@@ -59,14 +69,16 @@ class ListCollections implements Executable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      * @param string $databaseName Database name
      * @param array  $options      Command options
      * @throws InvalidArgumentException for parameter/option parsing errors
      */
     public function __construct($databaseName, array $options = [])
     {
+        if (isset($options['authorizedCollections']) && ! is_bool($options['authorizedCollections'])) {
+            throw InvalidArgumentException::invalidType('"authorizedCollections" option', $options['authorizedCollections'], 'boolean');
+        }
+
         if (isset($options['filter']) && ! is_array($options['filter']) && ! is_object($options['filter'])) {
             throw InvalidArgumentException::invalidType('"filter" option', $options['filter'], 'array or object');
         }
@@ -96,6 +108,19 @@ class ListCollections implements Executable
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
+    {
+        $cursor = $server->executeReadCommand($this->databaseName, $this->createCommand(), $this->createOptions());
+        $cursor->setTypeMap(['root' => 'array', 'document' => 'array']);
+
+        return new CachingIterator($cursor);
+    }
+
+    /**
+     * Create the listCollections command.
+     *
+     * @return Command
+     */
+    private function createCommand()
     {
         $cmd = ['listCollections' => 1];
 
@@ -103,18 +128,13 @@ class ListCollections implements Executable
             $cmd['filter'] = (object) $this->options['filter'];
         }
 
-        if (isset($this->options['maxTimeMS'])) {
-            $cmd['maxTimeMS'] = $this->options['maxTimeMS'];
+        foreach (['authorizedCollections', 'comment', 'maxTimeMS', 'nameOnly'] as $option) {
+            if (isset($this->options[$option])) {
+                $cmd[$option] = $this->options[$option];
+            }
         }
 
-        if (isset($this->options['nameOnly'])) {
-            $cmd['nameOnly'] = $this->options['nameOnly'];
-        }
-
-        $cursor = $server->executeReadCommand($this->databaseName, new Command($cmd), $this->createOptions());
-        $cursor->setTypeMap(['root' => 'array', 'document' => 'array']);
-
-        return new CachingIterator($cursor);
+        return new Command($cmd);
     }
 
     /**
@@ -123,7 +143,7 @@ class ListCollections implements Executable
      * Note: read preference is intentionally omitted, as the spec requires that
      * the command be executed on the primary.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executecommand.php
      * @return array
      */
     private function createOptions()

cache/stores/mongodb/MongoDB/Command/ListDatabases.php

@@ -6,7 +6,7 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -24,6 +24,7 @@ use MongoDB\Driver\Session;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnexpectedValueException;
 use MongoDB\Operation\Executable;
+
 use function current;
 use function is_array;
 use function is_bool;
@@ -34,7 +35,7 @@ use function is_object;
  * Wrapper for the ListDatabases command.
  *
  * @internal
- * @see http://docs.mongodb.org/manual/reference/command/listDatabases/
+ * @see https://mongodb.com/docs/manual/reference/command/listDatabases/
  */
 class ListDatabases implements Executable
 {
@@ -51,9 +52,11 @@ class ListDatabases implements Executable
      *
      *    For servers < 4.0.5, this option is ignored.
      *
-     *  * filter (document): Query by which to filter databases.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
      *
-     *    For servers < 3.6, this option is ignored.
+     *    This is not supported for servers versions < 4.4.
+     *
+     *  * filter (document): Query by which to filter databases.
      *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
      *    run.
@@ -64,8 +67,6 @@ class ListDatabases implements Executable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      * @param array $options Command options
      * @throws InvalidArgumentException for parameter/option parsing errors
      */
@@ -105,25 +106,7 @@ class ListDatabases implements Executable
      */
     public function execute(Server $server)
     {
-        $cmd = ['listDatabases' => 1];
-
-        if (isset($this->options['authorizedDatabases'])) {
-            $cmd['authorizedDatabases'] = $this->options['authorizedDatabases'];
-        }
-
-        if (! empty($this->options['filter'])) {
-            $cmd['filter'] = (object) $this->options['filter'];
-        }
-
-        if (isset($this->options['maxTimeMS'])) {
-            $cmd['maxTimeMS'] = $this->options['maxTimeMS'];
-        }
-
-        if (isset($this->options['nameOnly'])) {
-            $cmd['nameOnly'] = $this->options['nameOnly'];
-        }
-
-        $cursor = $server->executeReadCommand('admin', new Command($cmd), $this->createOptions());
+        $cursor = $server->executeReadCommand('admin', $this->createCommand(), $this->createOptions());
         $cursor->setTypeMap(['root' => 'array', 'document' => 'array']);
         $result = current($cursor->toArray());
 
@@ -134,13 +117,35 @@ class ListDatabases implements Executable
         return $result['databases'];
     }
 
+    /**
+     * Create the listDatabases command.
+     *
+     * @return Command
+     */
+    private function createCommand()
+    {
+        $cmd = ['listDatabases' => 1];
+
+        if (! empty($this->options['filter'])) {
+            $cmd['filter'] = (object) $this->options['filter'];
+        }
+
+        foreach (['authorizedDatabases', 'comment', 'maxTimeMS', 'nameOnly'] as $option) {
+            if (isset($this->options[$option])) {
+                $cmd[$option] = $this->options[$option];
+            }
+        }
+
+        return new Command($cmd);
+    }
+
     /**
      * Create options for executing the command.
      *
      * Note: read preference is intentionally omitted, as the spec requires that
      * the command be executed on the primary.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executecommand.php
      * @return array
      */
     private function createOptions()

cache/stores/mongodb/MongoDB/Database.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -33,14 +33,17 @@ use MongoDB\Model\BSONDocument;
 use MongoDB\Model\CollectionInfoIterator;
 use MongoDB\Operation\Aggregate;
 use MongoDB\Operation\CreateCollection;
+use MongoDB\Operation\CreateIndexes;
 use MongoDB\Operation\DatabaseCommand;
 use MongoDB\Operation\DropCollection;
 use MongoDB\Operation\DropDatabase;
 use MongoDB\Operation\ListCollectionNames;
 use MongoDB\Operation\ListCollections;
 use MongoDB\Operation\ModifyCollection;
+use MongoDB\Operation\RenameCollection;
 use MongoDB\Operation\Watch;
 use Traversable;
+
 use function is_array;
 use function strlen;
 
@@ -53,12 +56,6 @@ class Database
         'root' => BSONDocument::class,
     ];
 
-    /** @var integer */
-    private static $wireVersionForReadConcern = 4;
-
-    /** @var integer */
-    private static $wireVersionForWritableCommandWriteConcern = 5;
-
     /** @var integer */
     private static $wireVersionForReadConcernWithWriteStage = 8;
 
@@ -109,7 +106,7 @@ class Database
      */
     public function __construct(Manager $manager, $databaseName, array $options = [])
     {
-        if (strlen($databaseName) < 1) {
+        if (strlen((string) $databaseName) < 1) {
             throw new InvalidArgumentException('$databaseName is invalid: ' . $databaseName);
         }
 
@@ -140,7 +137,7 @@ class Database
     /**
      * Return internal properties for debugging purposes.
      *
-     * @see http://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
+     * @see https://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
      * @return array
      */
     public function __debugInfo()
@@ -162,8 +159,8 @@ class Database
      * be selected with complex syntax (e.g. $database->{"system.profile"}) or
      * {@link selectCollection()}.
      *
-     * @see http://php.net/oop5.overloading#object.get
-     * @see http://php.net/types.string#language.types.string.parsing.complex
+     * @see https://php.net/oop5.overloading#object.get
+     * @see https://php.net/types.string#language.types.string.parsing.complex
      * @param string $collectionName Name of the collection to select
      * @return Collection
      */
@@ -204,19 +201,17 @@ class Database
             $options['readPreference'] = $this->readPreference;
         }
 
-        if ($hasWriteStage) {
-            $options['readPreference'] = new ReadPreference(ReadPreference::RP_PRIMARY);
-        }
-
-        $server = select_server($this->manager, $options);
+        $server = $hasWriteStage
+            ? select_server_for_aggregate_write_stage($this->manager, $options)
+            : select_server($this->manager, $options);
 
         /* MongoDB 4.2 and later supports a read concern when an $out stage is
          * being used, but earlier versions do not.
          *
          * A read concern is also not compatible with transactions.
          */
-        if (! isset($options['readConcern']) &&
-            server_supports_feature($server, self::$wireVersionForReadConcern) &&
+        if (
+            ! isset($options['readConcern']) &&
             ! is_in_transaction($options) &&
             ( ! $hasWriteStage || server_supports_feature($server, self::$wireVersionForReadConcernWithWriteStage))
         ) {
@@ -227,10 +222,7 @@ class Database
             $options['typeMap'] = $this->typeMap;
         }
 
-        if ($hasWriteStage &&
-            ! isset($options['writeConcern']) &&
-            server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) &&
-            ! is_in_transaction($options)) {
+        if ($hasWriteStage && ! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -280,13 +272,34 @@ class Database
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
+        $encryptedFields = $options['encryptedFields']
+            ?? get_encrypted_fields_from_driver($this->databaseName, $collectionName, $this->manager)
+            ?? null;
+
+        if ($encryptedFields !== null) {
+            // encryptedFields is passed to the create command
+            $options['encryptedFields'] = $encryptedFields;
+
+            $encryptedFields = (array) $encryptedFields;
+            $enxcolOptions = ['clusteredIndex' => ['key' => ['_id' => 1], 'unique' => true]];
+            (new CreateCollection($this->databaseName, $encryptedFields['escCollection'] ?? 'enxcol_.' . $collectionName . '.esc', $enxcolOptions))->execute($server);
+            (new CreateCollection($this->databaseName, $encryptedFields['eccCollection'] ?? 'enxcol_.' . $collectionName . '.ecc', $enxcolOptions))->execute($server);
+            (new CreateCollection($this->databaseName, $encryptedFields['ecocCollection'] ?? 'enxcol_.' . $collectionName . '.ecoc', $enxcolOptions))->execute($server);
+        }
+
         $operation = new CreateCollection($this->databaseName, $collectionName, $options);
 
-        return $operation->execute($server);
+        $result = $operation->execute($server);
+
+        if ($encryptedFields !== null) {
+            (new CreateIndexes($this->databaseName, $collectionName, [['key' => ['__safeContent__' => 1]]]))->execute($server);
+        }
+
+        return $result;
     }
 
     /**
@@ -307,7 +320,7 @@ class Database
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -335,10 +348,25 @@ class Database
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
+        $encryptedFields = $options['encryptedFields']
+            ?? get_encrypted_fields_from_driver($this->databaseName, $collectionName, $this->manager)
+            ?? get_encrypted_fields_from_server($this->databaseName, $collectionName, $this->manager, $server)
+            ?? null;
+
+        if ($encryptedFields !== null) {
+            // encryptedFields is not passed to the drop command
+            unset($options['encryptedFields']);
+
+            $encryptedFields = (array) $encryptedFields;
+            (new DropCollection($this->databaseName, $encryptedFields['escCollection'] ?? 'enxcol_.' . $collectionName . '.esc'))->execute($server);
+            (new DropCollection($this->databaseName, $encryptedFields['eccCollection'] ?? 'enxcol_.' . $collectionName . '.ecc'))->execute($server);
+            (new DropCollection($this->databaseName, $encryptedFields['ecocCollection'] ?? 'enxcol_.' . $collectionName . '.ecoc'))->execute($server);
+        }
+
         $operation = new DropCollection($this->databaseName, $collectionName, $options);
 
         return $operation->execute($server);
@@ -367,7 +395,7 @@ class Database
     /**
      * Return the read concern for this database.
      *
-     * @see http://php.net/manual/en/mongodb-driver-readconcern.isdefault.php
+     * @see https://php.net/manual/en/mongodb-driver-readconcern.isdefault.php
      * @return ReadConcern
      */
     public function getReadConcern()
@@ -398,7 +426,7 @@ class Database
     /**
      * Return the write concern for this database.
      *
-     * @see http://php.net/manual/en/mongodb-driver-writeconcern.isdefault.php
+     * @see https://php.net/manual/en/mongodb-driver-writeconcern.isdefault.php
      * @return WriteConcern
      */
     public function getWriteConcern()
@@ -413,7 +441,7 @@ class Database
      * @throws InvalidArgumentException for parameter/option parsing errors
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
-    public function listCollectionNames(array $options = []) : Iterator
+    public function listCollectionNames(array $options = []): Iterator
     {
         $operation = new ListCollectionNames($this->databaseName, $options);
         $server = select_server($this->manager, $options);
@@ -457,7 +485,7 @@ class Database
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['writeConcern']) && server_supports_feature($server, self::$wireVersionForWritableCommandWriteConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
             $options['writeConcern'] = $this->writeConcern;
         }
 
@@ -466,6 +494,40 @@ class Database
         return $operation->execute($server);
     }
 
+    /**
+     * Rename a collection within this database.
+     *
+     * @see RenameCollection::__construct() for supported options
+     * @param string  $fromCollectionName Collection name
+     * @param string  $toCollectionName   New name of the collection
+     * @param ?string $toDatabaseName     New database name of the collection. Defaults to the original database.
+     * @param array   $options            Additional options
+     * @return array|object Command result document
+     * @throws UnsupportedException if options are unsupported on the selected server
+     * @throws InvalidArgumentException for parameter/option parsing errors
+     * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
+     */
+    public function renameCollection(string $fromCollectionName, string $toCollectionName, ?string $toDatabaseName = null, array $options = [])
+    {
+        if (! isset($toDatabaseName)) {
+            $toDatabaseName = $this->databaseName;
+        }
+
+        if (! isset($options['typeMap'])) {
+            $options['typeMap'] = $this->typeMap;
+        }
+
+        $server = select_server($this->manager, $options);
+
+        if (! isset($options['writeConcern']) && ! is_in_transaction($options)) {
+            $options['writeConcern'] = $this->writeConcern;
+        }
+
+        $operation = new RenameCollection($this->databaseName, $fromCollectionName, $toDatabaseName, $toCollectionName, $options);
+
+        return $operation->execute($server);
+    }
+
     /**
      * Select a collection within this database.
      *
@@ -524,7 +586,7 @@ class Database
 
         $server = select_server($this->manager, $options);
 
-        if (! isset($options['readConcern']) && server_supports_feature($server, self::$wireVersionForReadConcern) && ! is_in_transaction($options)) {
+        if (! isset($options['readConcern']) && ! is_in_transaction($options)) {
             $options['readConcern'] = $this->readConcern;
         }
 

cache/stores/mongodb/MongoDB/DeleteResult.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,

cache/stores/mongodb/MongoDB/Exception/BadMethodCallException.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,6 +18,7 @@
 namespace MongoDB\Exception;
 
 use BadMethodCallException as BaseBadMethodCallException;
+
 use function sprintf;
 
 class BadMethodCallException extends BaseBadMethodCallException implements Exception

cache/stores/mongodb/MongoDB/Exception/Exception.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,

cache/stores/mongodb/MongoDB/Exception/InvalidArgumentException.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,6 +18,7 @@
 namespace MongoDB\Exception;
 
 use MongoDB\Driver\Exception\InvalidArgumentException as DriverInvalidArgumentException;
+
 use function array_pop;
 use function count;
 use function get_debug_type;

cache/stores/mongodb/MongoDB/Exception/ResumeTokenException.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,

cache/stores/mongodb/MongoDB/Exception/RuntimeException.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,

cache/stores/mongodb/MongoDB/Exception/UnexpectedValueException.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,

cache/stores/mongodb/MongoDB/Exception/UnsupportedException.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -32,6 +32,9 @@ class UnsupportedException extends RuntimeException
     /**
      * Thrown when array filters are not supported by a server.
      *
+     * @deprecated 1.12
+     * @todo Remove this in 2.0 (see: PHPLIB-797)
+     *
      * @return self
      */
     public static function arrayFiltersNotSupported()
@@ -42,6 +45,9 @@ class UnsupportedException extends RuntimeException
     /**
      * Thrown when collations are not supported by a server.
      *
+     * @deprecated 1.12
+     * @todo Remove this in 2.0 (see: PHPLIB-797)
+     *
      * @return self
      */
     public static function collationNotSupported()

cache/stores/mongodb/MongoDB/GridFS/Bucket.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2016-2017 MongoDB, Inc.
+ * Copyright 2016-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -33,6 +33,7 @@ use MongoDB\Model\BSONArray;
 use MongoDB\Model\BSONDocument;
 use MongoDB\Operation\Find;
 use stdClass;
+
 use function array_intersect_key;
 use function fopen;
 use function get_resource_type;
@@ -195,7 +196,7 @@ class Bucket
     /**
      * Return internal properties for debugging purposes.
      *
-     * @see http://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
+     * @see https://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
      * @return array
      */
     public function __debugInfo()
@@ -433,7 +434,7 @@ class Bucket
     /**
      * Return the read concern for this GridFS bucket.
      *
-     * @see http://php.net/manual/en/mongodb-driver-readconcern.isdefault.php
+     * @see https://php.net/manual/en/mongodb-driver-readconcern.isdefault.php
      * @return ReadConcern
      */
     public function getReadConcern()
@@ -464,7 +465,7 @@ class Bucket
     /**
      * Return the write concern for this GridFS bucket.
      *
-     * @see http://php.net/manual/en/mongodb-driver-writeconcern.isdefault.php
+     * @see https://php.net/manual/en/mongodb-driver-writeconcern.isdefault.php
      * @return WriteConcern
      */
     public function getWriteConcern()
@@ -629,6 +630,7 @@ class Bucket
 
         if (@stream_copy_to_stream($source, $destination) === false) {
             $destinationUri = $this->createPathForFile($this->getRawFileDocumentForStream($destination));
+
             throw StreamException::uploadFailed($filename, $source, $destinationUri);
         }
 

cache/stores/mongodb/MongoDB/GridFS/CollectionWrapper.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2016-2017 MongoDB, Inc.
+ * Copyright 2016-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -26,6 +26,7 @@ use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\UpdateResult;
 use MultipleIterator;
 use stdClass;
+
 use function abs;
 use function count;
 use function is_numeric;
@@ -342,7 +343,7 @@ class CollectionWrapper
         $this->ensureChunksIndex();
     }
 
-    private function indexKeysMatch(array $expectedKeys, array $actualKeys) : bool
+    private function indexKeysMatch(array $expectedKeys, array $actualKeys): bool
     {
         if (count($expectedKeys) !== count($actualKeys)) {
             return false;
@@ -353,8 +354,8 @@ class CollectionWrapper
         $iterator->attachIterator(new ArrayIterator($actualKeys));
 
         foreach ($iterator as $key => $value) {
-            list($expectedKey, $actualKey)     = $key;
-            list($expectedValue, $actualValue) = $value;
+            [$expectedKey, $actualKey]     = $key;
+            [$expectedValue, $actualValue] = $value;
 
             if ($expectedKey !== $actualKey) {
                 return false;

cache/stores/mongodb/MongoDB/GridFS/Exception/CorruptFileException.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2016-2017 MongoDB, Inc.
+ * Copyright 2016-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,6 +18,7 @@
 namespace MongoDB\GridFS\Exception;
 
 use MongoDB\Exception\RuntimeException;
+
 use function sprintf;
 
 class CorruptFileException extends RuntimeException

cache/stores/mongodb/MongoDB/GridFS/Exception/FileNotFoundException.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2016-2017 MongoDB, Inc.
+ * Copyright 2016-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,6 +18,7 @@
 namespace MongoDB\GridFS\Exception;
 
 use MongoDB\Exception\RuntimeException;
+
 use function MongoDB\BSON\fromPHP;
 use function MongoDB\BSON\toJSON;
 use function sprintf;

cache/stores/mongodb/MongoDB/GridFS/Exception/StreamException.php

@@ -3,6 +3,7 @@
 namespace MongoDB\GridFS\Exception;
 
 use MongoDB\Exception\RuntimeException;
+
 use function MongoDB\BSON\fromPHP;
 use function MongoDB\BSON\toJSON;
 use function sprintf;
@@ -14,7 +15,7 @@ class StreamException extends RuntimeException
      * @param resource $source
      * @param resource $destination
      */
-    public static function downloadFromFilenameFailed(string $filename, $source, $destination) : self
+    public static function downloadFromFilenameFailed(string $filename, $source, $destination): self
     {
         $sourceMetadata = stream_get_meta_data($source);
         $destinationMetadata = stream_get_meta_data($destination);
@@ -27,7 +28,7 @@ class StreamException extends RuntimeException
      * @param resource $source
      * @param resource $destination
      */
-    public static function downloadFromIdFailed($id, $source, $destination) : self
+    public static function downloadFromIdFailed($id, $source, $destination): self
     {
         $idString = toJSON(fromPHP(['_id' => $id]));
         $sourceMetadata = stream_get_meta_data($source);
@@ -37,7 +38,7 @@ class StreamException extends RuntimeException
     }
 
     /** @param resource $source */
-    public static function uploadFailed(string $filename, $source, string $destinationUri) : self
+    public static function uploadFailed(string $filename, $source, string $destinationUri): self
     {
         $sourceMetadata = stream_get_meta_data($source);
 

cache/stores/mongodb/MongoDB/GridFS/ReadableStream.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2016-2017 MongoDB, Inc.
+ * Copyright 2016-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -17,10 +17,11 @@
 
 namespace MongoDB\GridFS;
 
-use IteratorIterator;
+use MongoDB\Driver\CursorInterface;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\GridFS\Exception\CorruptFileException;
 use stdClass;
+
 use function ceil;
 use function floor;
 use function is_integer;
@@ -48,7 +49,7 @@ class ReadableStream
     /** @var integer */
     private $chunkOffset = 0;
 
-    /** @var IteratorIterator|null */
+    /** @var CursorInterface|null */
     private $chunksIterator;
 
     /** @var CollectionWrapper */
@@ -95,14 +96,14 @@ class ReadableStream
 
         if ($this->length > 0) {
             $this->numChunks = (integer) ceil($this->length / $this->chunkSize);
-            $this->expectedLastChunkSize = ($this->length - (($this->numChunks - 1) * $this->chunkSize));
+            $this->expectedLastChunkSize = $this->length - (($this->numChunks - 1) * $this->chunkSize);
         }
     }
 
     /**
      * Return internal properties for debugging purposes.
      *
-     * @see http://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
+     * @see https://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
      * @return array
      */
     public function __debugInfo()
@@ -315,9 +316,7 @@ class ReadableStream
      */
     private function initChunksIterator()
     {
-        $cursor = $this->collectionWrapper->findChunksByFileId($this->file->_id, $this->chunkOffset);
-
-        $this->chunksIterator = new IteratorIterator($cursor);
+        $this->chunksIterator = $this->collectionWrapper->findChunksByFileId($this->file->_id, $this->chunkOffset);
         $this->chunksIterator->rewind();
     }
 }

cache/stores/mongodb/MongoDB/GridFS/StreamWrapper.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2016-2017 MongoDB, Inc.
+ * Copyright 2016-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -19,18 +19,15 @@ namespace MongoDB\GridFS;
 
 use MongoDB\BSON\UTCDateTime;
 use stdClass;
-use Throwable;
+
 use function explode;
-use function get_class;
 use function in_array;
 use function is_integer;
-use function sprintf;
 use function stream_context_get_options;
 use function stream_get_wrappers;
 use function stream_wrapper_register;
 use function stream_wrapper_unregister;
-use function trigger_error;
-use const E_USER_WARNING;
+
 use const SEEK_CUR;
 use const SEEK_END;
 use const SEEK_SET;
@@ -92,7 +89,7 @@ class StreamWrapper
     /**
      * Closes the stream.
      *
-     * @see http://php.net/manual/en/streamwrapper.stream-close.php
+     * @see https://php.net/manual/en/streamwrapper.stream-close.php
      */
     public function stream_close()
     {
@@ -106,7 +103,7 @@ class StreamWrapper
     /**
      * Returns whether the file pointer is at the end of the stream.
      *
-     * @see http://php.net/manual/en/streamwrapper.stream-eof.php
+     * @see https://php.net/manual/en/streamwrapper.stream-eof.php
      * @return boolean
      */
     public function stream_eof()
@@ -121,7 +118,7 @@ class StreamWrapper
     /**
      * Opens the stream.
      *
-     * @see http://php.net/manual/en/streamwrapper.stream-open.php
+     * @see https://php.net/manual/en/streamwrapper.stream-open.php
      * @param string  $path       Path to the file resource
      * @param string  $mode       Mode used to open the file (only "r" and "w" are supported)
      * @param integer $options    Additional flags set by the streams API
@@ -150,7 +147,7 @@ class StreamWrapper
      * Note: this method may return a string smaller than the requested length
      * if data is not available to be read.
      *
-     * @see http://php.net/manual/en/streamwrapper.stream-read.php
+     * @see https://php.net/manual/en/streamwrapper.stream-read.php
      * @param integer $length Number of bytes to read
      * @return string
      */
@@ -160,19 +157,13 @@ class StreamWrapper
             return '';
         }
 
-        try {
-            return $this->stream->readBytes($length);
-        } catch (Throwable $e) {
-            trigger_error(sprintf('%s: %s', get_class($e), $e->getMessage()), E_USER_WARNING);
-
-            return false;
-        }
+        return $this->stream->readBytes($length);
     }
 
     /**
      * Return the current position of the stream.
      *
-     * @see http://php.net/manual/en/streamwrapper.stream-seek.php
+     * @see https://php.net/manual/en/streamwrapper.stream-seek.php
      * @param integer $offset Stream offset to seek to
      * @param integer $whence One of SEEK_SET, SEEK_CUR, or SEEK_END
      * @return boolean True if the position was updated and false otherwise
@@ -206,7 +197,7 @@ class StreamWrapper
     /**
      * Return information about the stream.
      *
-     * @see http://php.net/manual/en/streamwrapper.stream-stat.php
+     * @see https://php.net/manual/en/streamwrapper.stream-stat.php
      * @return array
      */
     public function stream_stat()
@@ -236,7 +227,7 @@ class StreamWrapper
     /**
      * Return the current position of the stream.
      *
-     * @see http://php.net/manual/en/streamwrapper.stream-tell.php
+     * @see https://php.net/manual/en/streamwrapper.stream-tell.php
      * @return integer The current position of the stream
      */
     public function stream_tell()
@@ -247,7 +238,7 @@ class StreamWrapper
     /**
      * Write bytes to the stream.
      *
-     * @see http://php.net/manual/en/streamwrapper.stream-write.php
+     * @see https://php.net/manual/en/streamwrapper.stream-write.php
      * @param string $data Data to write
      * @return integer The number of bytes written
      */
@@ -257,13 +248,7 @@ class StreamWrapper
             return 0;
         }
 
-        try {
-            return $this->stream->writeBytes($data);
-        } catch (Throwable $e) {
-            trigger_error(sprintf('%s: %s', get_class($e), $e->getMessage()), E_USER_WARNING);
-
-            return false;
-        }
+        return $this->stream->writeBytes($data);
     }
 
     /**

cache/stores/mongodb/MongoDB/GridFS/WritableStream.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2016-2017 MongoDB, Inc.
+ * Copyright 2016-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -23,6 +23,7 @@ use MongoDB\BSON\UTCDateTime;
 use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
 use MongoDB\Exception\InvalidArgumentException;
 use stdClass;
+
 use function array_intersect_key;
 use function hash_final;
 use function hash_init;
@@ -152,7 +153,7 @@ class WritableStream
     /**
      * Return internal properties for debugging purposes.
      *
-     * @see http://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
+     * @see https://php.net/manual/en/language.oop5.magic.php#language.oop5.magic.debuginfo
      * @return array
      */
     public function __debugInfo()
@@ -261,6 +262,9 @@ class WritableStream
         $this->isClosed = true;
     }
 
+    /**
+     * @return mixed
+     */
     private function fileCollectionInsert()
     {
         $this->file['length'] = $this->length;

cache/stores/mongodb/MongoDB/InsertManyResult.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,

cache/stores/mongodb/MongoDB/InsertOneResult.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,

cache/stores/mongodb/MongoDB/MapReduceResult.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2017 MongoDB, Inc.
+ * Copyright 2017-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,8 +18,10 @@
 namespace MongoDB;
 
 use IteratorAggregate;
+use ReturnTypeWillChange;
 use stdClass;
 use Traversable;
+
 use function call_user_func;
 
 /**
@@ -31,7 +33,7 @@ use function call_user_func;
  *
  * @api
  * @see \MongoDB\Collection::mapReduce()
- * @see https://docs.mongodb.com/manual/reference/command/mapReduce/
+ * @see https://mongodb.com/docs/manual/reference/command/mapReduce/
  */
 class MapReduceResult implements IteratorAggregate
 {
@@ -83,9 +85,10 @@ class MapReduceResult implements IteratorAggregate
     /**
      * Return the mapReduce results as a Traversable.
      *
-     * @see http://php.net/iteratoraggregate.getiterator
+     * @see https://php.net/iteratoraggregate.getiterator
      * @return Traversable
      */
+    #[ReturnTypeWillChange]
     public function getIterator()
     {
         return call_user_func($this->getIterator);

cache/stores/mongodb/MongoDB/Model/BSONArray.php

@@ -6,7 +6,7 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -21,6 +21,8 @@ use ArrayObject;
 use JsonSerializable;
 use MongoDB\BSON\Serializable;
 use MongoDB\BSON\Unserializable;
+use ReturnTypeWillChange;
+
 use function array_values;
 use function MongoDB\recursive_copy;
 
@@ -47,8 +49,8 @@ class BSONArray extends ArrayObject implements JsonSerializable, Serializable, U
     /**
      * Factory method for var_export().
      *
-     * @see http://php.net/oop5.magic#object.set-state
-     * @see http://php.net/var-export
+     * @see https://php.net/oop5.magic#object.set-state
+     * @see https://php.net/var-export
      * @param array $properties
      * @return self
      */
@@ -66,7 +68,7 @@ class BSONArray extends ArrayObject implements JsonSerializable, Serializable, U
      * The array data will be numerically reindexed to ensure that it is stored
      * as a BSON array.
      *
-     * @see http://php.net/mongodb-bson-serializable.bsonserialize
+     * @see https://php.net/mongodb-bson-serializable.bsonserialize
      * @return array
      */
     public function bsonSerialize()
@@ -77,7 +79,7 @@ class BSONArray extends ArrayObject implements JsonSerializable, Serializable, U
     /**
      * Unserialize the document to BSON.
      *
-     * @see http://php.net/mongodb-bson-unserializable.bsonunserialize
+     * @see https://php.net/mongodb-bson-unserializable.bsonunserialize
      * @param array $data Array data
      */
     public function bsonUnserialize(array $data)
@@ -91,9 +93,10 @@ class BSONArray extends ArrayObject implements JsonSerializable, Serializable, U
      * The array data will be numerically reindexed to ensure that it is stored
      * as a JSON array.
      *
-     * @see http://php.net/jsonserializable.jsonserialize
+     * @see https://php.net/jsonserializable.jsonserialize
      * @return array
      */
+    #[ReturnTypeWillChange]
     public function jsonSerialize()
     {
         return array_values($this->getArrayCopy());

cache/stores/mongodb/MongoDB/Model/BSONDocument.php

@@ -6,7 +6,7 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -21,6 +21,8 @@ use ArrayObject;
 use JsonSerializable;
 use MongoDB\BSON\Serializable;
 use MongoDB\BSON\Unserializable;
+use ReturnTypeWillChange;
+
 use function MongoDB\recursive_copy;
 
 /**
@@ -47,21 +49,21 @@ class BSONDocument extends ArrayObject implements JsonSerializable, Serializable
      * This overrides the parent constructor to allow property access of entries
      * by default.
      *
-     * @see http://php.net/arrayobject.construct
+     * @see https://php.net/arrayobject.construct
      * @param array   $input
      * @param integer $flags
-     * @param string  $iterator_class
+     * @param string  $iteratorClass
      */
-    public function __construct($input = [], $flags = ArrayObject::ARRAY_AS_PROPS, $iterator_class = 'ArrayIterator')
+    public function __construct($input = [], $flags = ArrayObject::ARRAY_AS_PROPS, $iteratorClass = 'ArrayIterator')
     {
-        parent::__construct($input, $flags, $iterator_class);
+        parent::__construct($input, $flags, $iteratorClass);
     }
 
     /**
      * Factory method for var_export().
      *
-     * @see http://php.net/oop5.magic#object.set-state
-     * @see http://php.net/var-export
+     * @see https://php.net/oop5.magic#object.set-state
+     * @see https://php.net/var-export
      * @param array $properties
      * @return self
      */
@@ -76,7 +78,7 @@ class BSONDocument extends ArrayObject implements JsonSerializable, Serializable
     /**
      * Serialize the document to BSON.
      *
-     * @see http://php.net/mongodb-bson-serializable.bsonserialize
+     * @see https://php.net/mongodb-bson-serializable.bsonserialize
      * @return object
      */
     public function bsonSerialize()
@@ -87,7 +89,7 @@ class BSONDocument extends ArrayObject implements JsonSerializable, Serializable
     /**
      * Unserialize the document to BSON.
      *
-     * @see http://php.net/mongodb-bson-unserializable.bsonunserialize
+     * @see https://php.net/mongodb-bson-unserializable.bsonunserialize
      * @param array $data Array data
      */
     public function bsonUnserialize(array $data)
@@ -98,9 +100,10 @@ class BSONDocument extends ArrayObject implements JsonSerializable, Serializable
     /**
      * Serialize the array to JSON.
      *
-     * @see http://php.net/jsonserializable.jsonserialize
+     * @see https://php.net/jsonserializable.jsonserialize
      * @return object
      */
+    #[ReturnTypeWillChange]
     public function jsonSerialize()
     {
         return (object) $this->getArrayCopy();

cache/stores/mongodb/MongoDB/Model/BSONIterator.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2018 MongoDB, Inc.
+ * Copyright 2018-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -20,6 +20,8 @@ namespace MongoDB\Model;
 use Iterator;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnexpectedValueException;
+use ReturnTypeWillChange;
+
 use function is_array;
 use function MongoDB\BSON\toPHP;
 use function sprintf;
@@ -61,7 +63,7 @@ class BSONIterator implements Iterator
      *  * typeMap (array): Type map for BSON deserialization.
      *
      * @internal
-     * @see http://php.net/manual/en/function.mongodb.bson-tophp.php
+     * @see https://php.net/manual/en/function.mongodb.bson-tophp.php
      * @param string $data    Concatenated, valid, BSON-encoded documents
      * @param array  $options Iterator options
      * @throws InvalidArgumentException for parameter/option parsing errors
@@ -82,27 +84,30 @@ class BSONIterator implements Iterator
     }
 
     /**
-     * @see http://php.net/iterator.current
+     * @see https://php.net/iterator.current
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function current()
     {
         return $this->current;
     }
 
     /**
-     * @see http://php.net/iterator.key
+     * @see https://php.net/iterator.key
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function key()
     {
         return $this->key;
     }
 
     /**
-     * @see http://php.net/iterator.next
+     * @see https://php.net/iterator.next
      * @return void
      */
+    #[ReturnTypeWillChange]
     public function next()
     {
         $this->key++;
@@ -111,9 +116,10 @@ class BSONIterator implements Iterator
     }
 
     /**
-     * @see http://php.net/iterator.rewind
+     * @see https://php.net/iterator.rewind
      * @return void
      */
+    #[ReturnTypeWillChange]
     public function rewind()
     {
         $this->key = 0;
@@ -123,9 +129,10 @@ class BSONIterator implements Iterator
     }
 
     /**
-     * @see http://php.net/iterator.valid
+     * @see https://php.net/iterator.valid
      * @return boolean
      */
+    #[ReturnTypeWillChange]
     public function valid()
     {
         return $this->current !== null;
@@ -137,13 +144,13 @@ class BSONIterator implements Iterator
             return;
         }
 
-        if (($this->bufferLength - $this->position) < self::$bsonSize) {
+        if ($this->bufferLength - $this->position < self::$bsonSize) {
             throw new UnexpectedValueException(sprintf('Expected at least %d bytes; %d remaining', self::$bsonSize, $this->bufferLength - $this->position));
         }
 
-        list(,$documentLength) = unpack('V', substr($this->buffer, $this->position, self::$bsonSize));
+        [, $documentLength] = unpack('V', substr($this->buffer, $this->position, self::$bsonSize));
 
-        if (($this->bufferLength - $this->position) < $documentLength) {
+        if ($this->bufferLength - $this->position < $documentLength) {
             throw new UnexpectedValueException(sprintf('Expected %d bytes; %d remaining', $documentLength, $this->bufferLength - $this->position));
         }
 

cache/stores/mongodb/MongoDB/Model/CachingIterator.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2017 MongoDB, Inc.
+ * Copyright 2017-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -20,10 +20,11 @@ namespace MongoDB\Model;
 use Countable;
 use Iterator;
 use IteratorIterator;
+use ReturnTypeWillChange;
 use Traversable;
+
 use function count;
 use function current;
-use function key;
 use function next;
 use function reset;
 
@@ -38,10 +39,13 @@ use function reset;
  */
 class CachingIterator implements Countable, Iterator
 {
+    private const FIELD_KEY = 0;
+    private const FIELD_VALUE = 1;
+
     /** @var array */
     private $items = [];
 
-    /** @var IteratorIterator */
+    /** @var Iterator */
     private $iterator;
 
     /** @var boolean */
@@ -53,23 +57,24 @@ class CachingIterator implements Countable, Iterator
     /**
      * Initialize the iterator and stores the first item in the cache. This
      * effectively rewinds the Traversable and the wrapping IteratorIterator.
-     *  Additionally, this mimics behavior of the SPL iterators and allows users
-     * to omit an explicit call * to rewind() before using the other methods.
+     * Additionally, this mimics behavior of the SPL iterators and allows users
+     * to omit an explicit call to rewind() before using the other methods.
      *
      * @param Traversable $traversable
      */
     public function __construct(Traversable $traversable)
     {
-        $this->iterator = new IteratorIterator($traversable);
+        $this->iterator = $traversable instanceof Iterator ? $traversable : new IteratorIterator($traversable);
 
         $this->iterator->rewind();
         $this->storeCurrentItem();
     }
 
     /**
-     * @see http://php.net/countable.count
+     * @see https://php.net/countable.count
      * @return integer
      */
+    #[ReturnTypeWillChange]
     public function count()
     {
         $this->exhaustIterator();
@@ -78,27 +83,34 @@ class CachingIterator implements Countable, Iterator
     }
 
     /**
-     * @see http://php.net/iterator.current
+     * @see https://php.net/iterator.current
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function current()
     {
-        return current($this->items);
+        $currentItem = current($this->items);
+
+        return $currentItem !== false ? $currentItem[self::FIELD_VALUE] : false;
     }
 
     /**
-     * @see http://php.net/iterator.key
+     * @see https://php.net/iterator.key
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function key()
     {
-        return key($this->items);
+        $currentItem = current($this->items);
+
+        return $currentItem !== false ? $currentItem[self::FIELD_KEY] : null;
     }
 
     /**
-     * @see http://php.net/iterator.next
+     * @see https://php.net/iterator.next
      * @return void
      */
+    #[ReturnTypeWillChange]
     public function next()
     {
         if (! $this->iteratorExhausted) {
@@ -114,9 +126,10 @@ class CachingIterator implements Countable, Iterator
     }
 
     /**
-     * @see http://php.net/iterator.rewind
+     * @see https://php.net/iterator.rewind
      * @return void
      */
+    #[ReturnTypeWillChange]
     public function rewind()
     {
         /* If the iterator has advanced, exhaust it now so that future iteration
@@ -130,9 +143,10 @@ class CachingIterator implements Countable, Iterator
     }
 
     /**
-     * @see http://php.net/iterator.valid
+     * @see https://php.net/iterator.valid
      * @return boolean
      */
+    #[ReturnTypeWillChange]
     public function valid()
     {
         return $this->key() !== null;
@@ -153,12 +167,14 @@ class CachingIterator implements Countable, Iterator
      */
     private function storeCurrentItem()
     {
-        $key = $this->iterator->key();
-
-        if ($key === null) {
+        if (! $this->iterator->valid()) {
             return;
         }
 
-        $this->items[$key] = $this->iterator->current();
+        // Storing a new item in the internal cache
+        $this->items[] = [
+            self::FIELD_KEY => $this->iterator->key(),
+            self::FIELD_VALUE => $this->iterator->current(),
+        ];
     }
 }

cache/stores/mongodb/MongoDB/Model/CallbackIterator.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2017 MongoDB, Inc.
+ * Copyright 2017-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -20,6 +20,7 @@ namespace MongoDB\Model;
 use Closure;
 use Iterator;
 use IteratorIterator;
+use ReturnTypeWillChange;
 use Traversable;
 
 /**
@@ -32,55 +33,60 @@ class CallbackIterator implements Iterator
     /** @var Closure */
     private $callback;
 
-    /** @var IteratorIterator */
+    /** @var Iterator */
     private $iterator;
 
     public function __construct(Traversable $traversable, Closure $callback)
     {
-        $this->iterator = new IteratorIterator($traversable);
+        $this->iterator = $traversable instanceof Iterator ? $traversable : new IteratorIterator($traversable);
         $this->callback = $callback;
     }
 
     /**
-     * @see http://php.net/iterator.current
+     * @see https://php.net/iterator.current
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function current()
     {
         return ($this->callback)($this->iterator->current());
     }
 
     /**
-     * @see http://php.net/iterator.key
+     * @see https://php.net/iterator.key
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function key()
     {
         return $this->iterator->key();
     }
 
     /**
-     * @see http://php.net/iterator.next
+     * @see https://php.net/iterator.next
      * @return void
      */
+    #[ReturnTypeWillChange]
     public function next()
     {
         $this->iterator->next();
     }
 
     /**
-     * @see http://php.net/iterator.rewind
+     * @see https://php.net/iterator.rewind
      * @return void
      */
+    #[ReturnTypeWillChange]
     public function rewind()
     {
         $this->iterator->rewind();
     }
 
     /**
-     * @see http://php.net/iterator.valid
+     * @see https://php.net/iterator.valid
      * @return boolean
      */
+    #[ReturnTypeWillChange]
     public function valid()
     {
         return $this->iterator->valid();

cache/stores/mongodb/MongoDB/Model/ChangeStreamIterator.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2019 MongoDB, Inc.
+ * Copyright 2019-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -28,6 +28,8 @@ use MongoDB\Driver\Server;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\ResumeTokenException;
 use MongoDB\Exception\UnexpectedValueException;
+use ReturnTypeWillChange;
+
 use function count;
 use function is_array;
 use function is_integer;
@@ -138,6 +140,7 @@ class ChangeStreamIterator extends IteratorIterator implements CommandSubscriber
      * @see https://php.net/iteratoriterator.current
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function current()
     {
         return $this->isValid ? parent::current() : null;
@@ -160,7 +163,7 @@ class ChangeStreamIterator extends IteratorIterator implements CommandSubscriber
     /**
      * Returns the server the cursor is running on.
      */
-    public function getServer() : Server
+    public function getServer(): Server
     {
         return $this->server;
     }
@@ -169,6 +172,7 @@ class ChangeStreamIterator extends IteratorIterator implements CommandSubscriber
      * @see https://php.net/iteratoriterator.key
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function key()
     {
         return $this->isValid ? parent::key() : null;
@@ -178,6 +182,7 @@ class ChangeStreamIterator extends IteratorIterator implements CommandSubscriber
      * @see https://php.net/iteratoriterator.rewind
      * @return void
      */
+    #[ReturnTypeWillChange]
     public function next()
     {
         /* Determine if advancing the iterator will execute a getMore command
@@ -205,6 +210,7 @@ class ChangeStreamIterator extends IteratorIterator implements CommandSubscriber
      * @see https://php.net/iteratoriterator.rewind
      * @return void
      */
+    #[ReturnTypeWillChange]
     public function rewind()
     {
         if ($this->isRewindNop) {
@@ -219,6 +225,7 @@ class ChangeStreamIterator extends IteratorIterator implements CommandSubscriber
      * @see https://php.net/iteratoriterator.valid
      * @return boolean
      */
+    #[ReturnTypeWillChange]
     public function valid()
     {
         return $this->isValid;
@@ -248,11 +255,13 @@ class ChangeStreamIterator extends IteratorIterator implements CommandSubscriber
 
         if (! isset($resumeToken)) {
             $this->isValid = false;
+
             throw ResumeTokenException::notFound();
         }
 
         if (! is_array($resumeToken) && ! is_object($resumeToken)) {
             $this->isValid = false;
+
             throw ResumeTokenException::invalidType($resumeToken);
         }
 

cache/stores/mongodb/MongoDB/Model/CollectionInfo.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -19,6 +19,8 @@ namespace MongoDB\Model;
 
 use ArrayAccess;
 use MongoDB\Exception\BadMethodCallException;
+use ReturnTypeWillChange;
+
 use function array_key_exists;
 
 /**
@@ -48,7 +50,7 @@ class CollectionInfo implements ArrayAccess
     /**
      * Return the collection info as an array.
      *
-     * @see http://php.net/oop5.magic#language.oop5.magic.debuginfo
+     * @see https://php.net/oop5.magic#language.oop5.magic.debuginfo
      * @return array
      */
     public function __debugInfo()
@@ -59,6 +61,8 @@ class CollectionInfo implements ArrayAccess
     /**
      * Return the maximum number of documents to keep in the capped collection.
      *
+     * @deprecated 1.0 Deprecated in favor of using getOptions
+     *
      * @return integer|null
      */
     public function getCappedMax()
@@ -70,6 +74,8 @@ class CollectionInfo implements ArrayAccess
     /**
      * Return the maximum size (in bytes) of the capped collection.
      *
+     * @deprecated 1.0 Deprecated in favor of using getOptions
+     *
      * @return integer|null
      */
     public function getCappedSize()
@@ -78,9 +84,31 @@ class CollectionInfo implements ArrayAccess
         return isset($this->info['options']['size']) ? (integer) $this->info['options']['size'] : null;
     }
 
+    /**
+     * Return information about the _id index for the collection.
+     *
+     * @return array
+     */
+    public function getIdIndex(): array
+    {
+        return (array) ($this->info['idIndex'] ?? []);
+    }
+
+    /**
+     * Return the "info" property of the server response.
+     *
+     * @see https://mongodb.com/docs/manual/reference/command/listCollections/#output
+     * @return array
+     */
+    public function getInfo(): array
+    {
+        return (array) ($this->info['info'] ?? []);
+    }
+
     /**
      * Return the collection name.
      *
+     * @see https://mongodb.com/docs/manual/reference/command/listCollections/#output
      * @return string
      */
     public function getName()
@@ -91,16 +119,30 @@ class CollectionInfo implements ArrayAccess
     /**
      * Return the collection options.
      *
+     * @see https://mongodb.com/docs/manual/reference/command/listCollections/#output
      * @return array
      */
     public function getOptions()
     {
-        return isset($this->info['options']) ? (array) $this->info['options'] : [];
+        return (array) ($this->info['options'] ?? []);
+    }
+
+    /**
+     * Return the collection type.
+     *
+     * @see https://mongodb.com/docs/manual/reference/command/listCollections/#output
+     * @return string
+     */
+    public function getType(): string
+    {
+        return (string) $this->info['type'];
     }
 
     /**
      * Return whether the collection is a capped collection.
      *
+     * @deprecated 1.0 Deprecated in favor of using getOptions
+     *
      * @return boolean
      */
     public function isCapped()
@@ -111,10 +153,11 @@ class CollectionInfo implements ArrayAccess
     /**
      * Check whether a field exists in the collection information.
      *
-     * @see http://php.net/arrayaccess.offsetexists
+     * @see https://php.net/arrayaccess.offsetexists
      * @param mixed $key
      * @return boolean
      */
+    #[ReturnTypeWillChange]
     public function offsetExists($key)
     {
         return array_key_exists($key, $this->info);
@@ -123,10 +166,11 @@ class CollectionInfo implements ArrayAccess
     /**
      * Return the field's value from the collection information.
      *
-     * @see http://php.net/arrayaccess.offsetget
+     * @see https://php.net/arrayaccess.offsetget
      * @param mixed $key
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function offsetGet($key)
     {
         return $this->info[$key];
@@ -135,11 +179,13 @@ class CollectionInfo implements ArrayAccess
     /**
      * Not supported.
      *
-     * @see http://php.net/arrayaccess.offsetset
+     * @see https://php.net/arrayaccess.offsetset
      * @param mixed $key
      * @param mixed $value
      * @throws BadMethodCallException
+     * @return void
      */
+    #[ReturnTypeWillChange]
     public function offsetSet($key, $value)
     {
         throw BadMethodCallException::classIsImmutable(self::class);
@@ -148,10 +194,12 @@ class CollectionInfo implements ArrayAccess
     /**
      * Not supported.
      *
-     * @see http://php.net/arrayaccess.offsetunset
+     * @see https://php.net/arrayaccess.offsetunset
      * @param mixed $key
      * @throws BadMethodCallException
+     * @return void
      */
+    #[ReturnTypeWillChange]
     public function offsetUnset($key)
     {
         throw BadMethodCallException::classIsImmutable(self::class);

cache/stores/mongodb/MongoDB/Model/CollectionInfoCommandIterator.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,6 +18,7 @@
 namespace MongoDB\Model;
 
 use IteratorIterator;
+use ReturnTypeWillChange;
 use Traversable;
 
 /**
@@ -29,7 +30,7 @@ use Traversable;
  * @internal
  * @see \MongoDB\Database::listCollections()
  * @see https://github.com/mongodb/specifications/blob/master/source/enumerate-collections.rst
- * @see http://docs.mongodb.org/manual/reference/command/listCollections/
+ * @see https://mongodb.com/docs/manual/reference/command/listCollections/
  */
 class CollectionInfoCommandIterator extends IteratorIterator implements CollectionInfoIterator
 {
@@ -50,9 +51,10 @@ class CollectionInfoCommandIterator extends IteratorIterator implements Collecti
      * Return the current element as a CollectionInfo instance.
      *
      * @see CollectionInfoIterator::current()
-     * @see http://php.net/iterator.current
+     * @see https://php.net/iterator.current
      * @return CollectionInfo
      */
+    #[ReturnTypeWillChange]
     public function current()
     {
         $info = parent::current();

cache/stores/mongodb/MongoDB/Model/CollectionInfoIterator.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,6 +18,7 @@
 namespace MongoDB\Model;
 
 use Iterator;
+use ReturnTypeWillChange;
 
 /**
  * CollectionInfoIterator interface.
@@ -34,5 +35,6 @@ interface CollectionInfoIterator extends Iterator
      *
      * @return CollectionInfo
      */
+    #[ReturnTypeWillChange]
     public function current();
 }

cache/stores/mongodb/MongoDB/Model/DatabaseInfo.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -19,6 +19,8 @@ namespace MongoDB\Model;
 
 use ArrayAccess;
 use MongoDB\Exception\BadMethodCallException;
+use ReturnTypeWillChange;
+
 use function array_key_exists;
 
 /**
@@ -29,7 +31,7 @@ use function array_key_exists;
  *
  * @api
  * @see \MongoDB\Client::listDatabases()
- * @see http://docs.mongodb.org/manual/reference/command/listDatabases/
+ * @see https://mongodb.com/docs/manual/reference/command/listDatabases/
  */
 class DatabaseInfo implements ArrayAccess
 {
@@ -47,7 +49,7 @@ class DatabaseInfo implements ArrayAccess
     /**
      * Return the database info as an array.
      *
-     * @see http://php.net/oop5.magic#language.oop5.magic.debuginfo
+     * @see https://php.net/oop5.magic#language.oop5.magic.debuginfo
      * @return array
      */
     public function __debugInfo()
@@ -89,10 +91,11 @@ class DatabaseInfo implements ArrayAccess
     /**
      * Check whether a field exists in the database information.
      *
-     * @see http://php.net/arrayaccess.offsetexists
+     * @see https://php.net/arrayaccess.offsetexists
      * @param mixed $key
      * @return boolean
      */
+    #[ReturnTypeWillChange]
     public function offsetExists($key)
     {
         return array_key_exists($key, $this->info);
@@ -101,10 +104,11 @@ class DatabaseInfo implements ArrayAccess
     /**
      * Return the field's value from the database information.
      *
-     * @see http://php.net/arrayaccess.offsetget
+     * @see https://php.net/arrayaccess.offsetget
      * @param mixed $key
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function offsetGet($key)
     {
         return $this->info[$key];
@@ -113,11 +117,13 @@ class DatabaseInfo implements ArrayAccess
     /**
      * Not supported.
      *
-     * @see http://php.net/arrayaccess.offsetset
+     * @see https://php.net/arrayaccess.offsetset
      * @param mixed $key
      * @param mixed $value
      * @throws BadMethodCallException
+     * @return void
      */
+    #[ReturnTypeWillChange]
     public function offsetSet($key, $value)
     {
         throw BadMethodCallException::classIsImmutable(self::class);
@@ -126,10 +132,12 @@ class DatabaseInfo implements ArrayAccess
     /**
      * Not supported.
      *
-     * @see http://php.net/arrayaccess.offsetunset
+     * @see https://php.net/arrayaccess.offsetunset
      * @param mixed $key
      * @throws BadMethodCallException
+     * @return void
      */
+    #[ReturnTypeWillChange]
     public function offsetUnset($key)
     {
         throw BadMethodCallException::classIsImmutable(self::class);

cache/stores/mongodb/MongoDB/Model/DatabaseInfoIterator.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,6 +18,7 @@
 namespace MongoDB\Model;
 
 use Iterator;
+use ReturnTypeWillChange;
 
 /**
  * DatabaseInfoIterator interface.
@@ -34,5 +35,6 @@ interface DatabaseInfoIterator extends Iterator
      *
      * @return DatabaseInfo
      */
+    #[ReturnTypeWillChange]
     public function current();
 }

cache/stores/mongodb/MongoDB/Model/DatabaseInfoLegacyIterator.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -17,6 +17,8 @@
 
 namespace MongoDB\Model;
 
+use ReturnTypeWillChange;
+
 use function current;
 use function key;
 use function next;
@@ -30,7 +32,7 @@ use function reset;
  *
  * @internal
  * @see \MongoDB\Client::listDatabases()
- * @see http://docs.mongodb.org/manual/reference/command/listDatabases/
+ * @see https://mongodb.com/docs/manual/reference/command/listDatabases/
  */
 class DatabaseInfoLegacyIterator implements DatabaseInfoIterator
 {
@@ -49,7 +51,7 @@ class DatabaseInfoLegacyIterator implements DatabaseInfoIterator
      * Return the current element as a DatabaseInfo instance.
      *
      * @see DatabaseInfoIterator::current()
-     * @see http://php.net/iterator.current
+     * @see https://php.net/iterator.current
      * @return DatabaseInfo
      */
     public function current()
@@ -60,9 +62,10 @@ class DatabaseInfoLegacyIterator implements DatabaseInfoIterator
     /**
      * Return the key of the current element.
      *
-     * @see http://php.net/iterator.key
+     * @see https://php.net/iterator.key
      * @return integer
      */
+    #[ReturnTypeWillChange]
     public function key()
     {
         return key($this->databases);
@@ -71,8 +74,10 @@ class DatabaseInfoLegacyIterator implements DatabaseInfoIterator
     /**
      * Move forward to next element.
      *
-     * @see http://php.net/iterator.next
+     * @see https://php.net/iterator.next
+     * @return void
      */
+    #[ReturnTypeWillChange]
     public function next()
     {
         next($this->databases);
@@ -81,8 +86,10 @@ class DatabaseInfoLegacyIterator implements DatabaseInfoIterator
     /**
      * Rewind the Iterator to the first element.
      *
-     * @see http://php.net/iterator.rewind
+     * @see https://php.net/iterator.rewind
+     * @return void
      */
+    #[ReturnTypeWillChange]
     public function rewind()
     {
         reset($this->databases);
@@ -91,9 +98,10 @@ class DatabaseInfoLegacyIterator implements DatabaseInfoIterator
     /**
      * Checks if current position is valid.
      *
-     * @see http://php.net/iterator.valid
+     * @see https://php.net/iterator.valid
      * @return boolean
      */
+    #[ReturnTypeWillChange]
     public function valid()
     {
         return key($this->databases) !== null;

cache/stores/mongodb/MongoDB/Model/IndexInfo.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -19,6 +19,8 @@ namespace MongoDB\Model;
 
 use ArrayAccess;
 use MongoDB\Exception\BadMethodCallException;
+use ReturnTypeWillChange;
+
 use function array_key_exists;
 use function array_search;
 
@@ -35,7 +37,7 @@ use function array_search;
  * @api
  * @see \MongoDB\Collection::listIndexes()
  * @see https://github.com/mongodb/specifications/blob/master/source/enumerate-indexes.rst
- * @see http://docs.mongodb.org/manual/reference/method/db.collection.createIndex/
+ * @see https://mongodb.com/docs/manual/reference/method/db.collection.createIndex/
  */
 class IndexInfo implements ArrayAccess
 {
@@ -53,7 +55,7 @@ class IndexInfo implements ArrayAccess
     /**
      * Return the collection info as an array.
      *
-     * @see http://php.net/oop5.magic#language.oop5.magic.debuginfo
+     * @see https://php.net/oop5.magic#language.oop5.magic.debuginfo
      * @return array
      */
     public function __debugInfo()
@@ -134,7 +136,7 @@ class IndexInfo implements ArrayAccess
     /**
      * Return whether this is a sparse index.
      *
-     * @see http://docs.mongodb.org/manual/core/index-sparse/
+     * @see https://mongodb.com/docs/manual/core/index-sparse/
      * @return boolean
      */
     public function isSparse()
@@ -155,7 +157,7 @@ class IndexInfo implements ArrayAccess
     /**
      * Return whether this is a TTL index.
      *
-     * @see http://docs.mongodb.org/manual/core/index-ttl/
+     * @see https://mongodb.com/docs/manual/core/index-ttl/
      * @return boolean
      */
     public function isTtl()
@@ -166,7 +168,7 @@ class IndexInfo implements ArrayAccess
     /**
      * Return whether this is a unique index.
      *
-     * @see http://docs.mongodb.org/manual/core/index-unique/
+     * @see https://mongodb.com/docs/manual/core/index-unique/
      * @return boolean
      */
     public function isUnique()
@@ -177,10 +179,11 @@ class IndexInfo implements ArrayAccess
     /**
      * Check whether a field exists in the index information.
      *
-     * @see http://php.net/arrayaccess.offsetexists
+     * @see https://php.net/arrayaccess.offsetexists
      * @param mixed $key
      * @return boolean
      */
+    #[ReturnTypeWillChange]
     public function offsetExists($key)
     {
         return array_key_exists($key, $this->info);
@@ -193,11 +196,12 @@ class IndexInfo implements ArrayAccess
      * that index fields be made accessible under their original names. It may
      * also be used to access fields that do not have a helper method.
      *
-     * @see http://php.net/arrayaccess.offsetget
+     * @see https://php.net/arrayaccess.offsetget
      * @see https://github.com/mongodb/specifications/blob/master/source/enumerate-indexes.rst#getting-full-index-information
      * @param mixed $key
      * @return mixed
      */
+    #[ReturnTypeWillChange]
     public function offsetGet($key)
     {
         return $this->info[$key];
@@ -206,11 +210,13 @@ class IndexInfo implements ArrayAccess
     /**
      * Not supported.
      *
-     * @see http://php.net/arrayaccess.offsetset
+     * @see https://php.net/arrayaccess.offsetset
      * @param mixed $key
      * @param mixed $value
      * @throws BadMethodCallException
+     * @return void
      */
+    #[ReturnTypeWillChange]
     public function offsetSet($key, $value)
     {
         throw BadMethodCallException::classIsImmutable(self::class);
@@ -219,10 +225,12 @@ class IndexInfo implements ArrayAccess
     /**
      * Not supported.
      *
-     * @see http://php.net/arrayaccess.offsetunset
+     * @see https://php.net/arrayaccess.offsetunset
      * @param mixed $key
      * @throws BadMethodCallException
+     * @return void
      */
+    #[ReturnTypeWillChange]
     public function offsetUnset($key)
     {
         throw BadMethodCallException::classIsImmutable(self::class);

cache/stores/mongodb/MongoDB/Model/IndexInfoIterator.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,6 +18,7 @@
 namespace MongoDB\Model;
 
 use Iterator;
+use ReturnTypeWillChange;
 
 /**
  * IndexInfoIterator interface.
@@ -34,5 +35,6 @@ interface IndexInfoIterator extends Iterator
      *
      * @return IndexInfo
      */
+    #[ReturnTypeWillChange]
     public function current();
 }

cache/stores/mongodb/MongoDB/Model/IndexInfoIteratorIterator.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,7 +18,9 @@
 namespace MongoDB\Model;
 
 use IteratorIterator;
+use ReturnTypeWillChange;
 use Traversable;
+
 use function array_key_exists;
 
 /**
@@ -31,8 +33,8 @@ use function array_key_exists;
  * @internal
  * @see \MongoDB\Collection::listIndexes()
  * @see https://github.com/mongodb/specifications/blob/master/source/enumerate-indexes.rst
- * @see http://docs.mongodb.org/manual/reference/command/listIndexes/
- * @see http://docs.mongodb.org/manual/reference/system-collections/
+ * @see https://mongodb.com/docs/manual/reference/command/listIndexes/
+ * @see https://mongodb.com/docs/manual/reference/system-collections/
  */
 class IndexInfoIteratorIterator extends IteratorIterator implements IndexInfoIterator
 {
@@ -53,9 +55,10 @@ class IndexInfoIteratorIterator extends IteratorIterator implements IndexInfoIte
      * Return the current element as an IndexInfo instance.
      *
      * @see IndexInfoIterator::current()
-     * @see http://php.net/iterator.current
+     * @see https://php.net/iterator.current
      * @return IndexInfo
      */
+    #[ReturnTypeWillChange]
     public function current()
     {
         $info = parent::current();

cache/stores/mongodb/MongoDB/Model/IndexInput.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -19,6 +19,7 @@ namespace MongoDB\Model;
 
 use MongoDB\BSON\Serializable;
 use MongoDB\Exception\InvalidArgumentException;
+
 use function is_array;
 use function is_float;
 use function is_int;
@@ -35,7 +36,7 @@ use function sprintf;
  * @internal
  * @see \MongoDB\Collection::createIndexes()
  * @see https://github.com/mongodb/specifications/blob/master/source/enumerate-indexes.rst
- * @see http://docs.mongodb.org/manual/reference/method/db.collection.createIndex/
+ * @see https://mongodb.com/docs/manual/reference/method/db.collection.createIndex/
  */
 class IndexInput implements Serializable
 {
@@ -87,7 +88,7 @@ class IndexInput implements Serializable
      * Serialize the index information to BSON for index creation.
      *
      * @see \MongoDB\Collection::createIndexes()
-     * @see http://php.net/mongodb-bson-serializable.bsonserialize
+     * @see https://php.net/mongodb-bson-serializable.bsonserialize
      * @return array
      */
     public function bsonSerialize()

cache/stores/mongodb/MongoDB/Operation/Aggregate.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -19,6 +19,7 @@ namespace MongoDB\Operation;
 
 use ArrayIterator;
 use MongoDB\Driver\Command;
+use MongoDB\Driver\Cursor;
 use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
 use MongoDB\Driver\ReadConcern;
 use MongoDB\Driver\ReadPreference;
@@ -30,6 +31,7 @@ use MongoDB\Exception\UnexpectedValueException;
 use MongoDB\Exception\UnsupportedException;
 use stdClass;
 use Traversable;
+
 use function current;
 use function is_array;
 use function is_bool;
@@ -38,7 +40,6 @@ use function is_object;
 use function is_string;
 use function MongoDB\create_field_path_type_map;
 use function MongoDB\is_last_pipeline_operator_write;
-use function MongoDB\server_supports_feature;
 use function sprintf;
 
 /**
@@ -46,22 +47,10 @@ use function sprintf;
  *
  * @api
  * @see \MongoDB\Collection::aggregate()
- * @see http://docs.mongodb.org/manual/reference/command/aggregate/
+ * @see https://mongodb.com/docs/manual/reference/command/aggregate/
  */
 class Aggregate implements Executable, Explainable
 {
-    /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var integer */
-    private static $wireVersionForDocumentLevelValidation = 4;
-
-    /** @var integer */
-    private static $wireVersionForReadConcern = 4;
-
-    /** @var integer */
-    private static $wireVersionForWriteConcern = 5;
-
     /** @var string */
     private $databaseName;
 
@@ -74,6 +63,12 @@ class Aggregate implements Executable, Explainable
     /** @var array */
     private $options;
 
+    /** @var bool */
+    private $isExplain;
+
+    /** @var bool */
+    private $isWrite;
+
     /**
      * Constructs an aggregate command.
      *
@@ -81,7 +76,7 @@ class Aggregate implements Executable, Explainable
      *
      *  * allowDiskUse (boolean): Enables writing to temporary files. When set
      *    to true, aggregation stages can write data to the _tmp sub-directory
-     *    in the dbPath directory. The default is false.
+     *    in the dbPath directory.
      *
      *  * batchSize (integer): The number of documents to return per batch.
      *
@@ -89,16 +84,11 @@ class Aggregate implements Executable, Explainable
      *    circumvent document level validation. This only applies when an $out
      *    or $merge stage is specified.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
-     *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
      *
-     *  * comment (string): An arbitrary string to help trace the operation
-     *    through the database profiler, currentOp, and logs.
+     *    Only string values are supported for server versions < 4.4.
      *
      *  * explain (boolean): Specifies whether or not to return the information
      *    on the processing of the pipeline.
@@ -107,22 +97,25 @@ class Aggregate implements Executable, Explainable
      *    name as a string or the index key pattern as a document. If specified,
      *    then the query system will only consider plans using the hinted index.
      *
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
+     *
+     *    This is not supported for server versions < 5.0 and will result in an
+     *    exception at execution time if used.
+     *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
      *    run.
      *
      *  * readConcern (MongoDB\Driver\ReadConcern): Read concern.
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
-     *
      *  * readPreference (MongoDB\Driver\ReadPreference): Read preference.
      *
      *    This option is ignored if an $out or $merge stage is specified.
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * typeMap (array): Type map for BSON deserialization. This will be
      *    applied to the returned Cursor (it is not sent to the server).
      *
@@ -135,9 +128,6 @@ class Aggregate implements Executable, Explainable
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern. This only
      *    applies when an $out or $merge stage is specified.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
-     *
      * Note: Collection-agnostic commands (e.g. $currentOp) may be executed by
      * specifying null for the collection name.
      *
@@ -163,12 +153,9 @@ class Aggregate implements Executable, Explainable
             $expectedIndex += 1;
         }
 
-        $options += [
-            'allowDiskUse' => false,
-            'useCursor' => true,
-        ];
+        $options += ['useCursor' => true];
 
-        if (! is_bool($options['allowDiskUse'])) {
+        if (isset($options['allowDiskUse']) && ! is_bool($options['allowDiskUse'])) {
             throw InvalidArgumentException::invalidType('"allowDiskUse" option', $options['allowDiskUse'], 'boolean');
         }
 
@@ -184,10 +171,6 @@ class Aggregate implements Executable, Explainable
             throw InvalidArgumentException::invalidType('"collation" option', $options['collation'], 'array or object');
         }
 
-        if (isset($options['comment']) && ! is_string($options['comment'])) {
-            throw InvalidArgumentException::invalidType('"comment" option', $options['comment'], 'string');
-        }
-
         if (isset($options['explain']) && ! is_bool($options['explain'])) {
             throw InvalidArgumentException::invalidType('"explain" option', $options['explain'], 'boolean');
         }
@@ -196,6 +179,10 @@ class Aggregate implements Executable, Explainable
             throw InvalidArgumentException::invalidType('"hint" option', $options['hint'], 'string or array or object');
         }
 
+        if (isset($options['let']) && ! is_array($options['let']) && ! is_object($options['let'])) {
+            throw InvalidArgumentException::invalidType('"let" option', $options['let'], ['array', 'object']);
+        }
+
         if (isset($options['maxAwaitTimeMS']) && ! is_integer($options['maxAwaitTimeMS'])) {
             throw InvalidArgumentException::invalidType('"maxAwaitTimeMS" option', $options['maxAwaitTimeMS'], 'integer');
         }
@@ -232,6 +219,10 @@ class Aggregate implements Executable, Explainable
             throw new InvalidArgumentException('"batchSize" option should not be used if "useCursor" is false');
         }
 
+        if (isset($options['bypassDocumentValidation']) && ! $options['bypassDocumentValidation']) {
+            unset($options['bypassDocumentValidation']);
+        }
+
         if (isset($options['readConcern']) && $options['readConcern']->isDefault()) {
             unset($options['readConcern']);
         }
@@ -240,8 +231,19 @@ class Aggregate implements Executable, Explainable
             unset($options['writeConcern']);
         }
 
-        if (! empty($options['explain'])) {
+        $this->isExplain = ! empty($options['explain']);
+        $this->isWrite = is_last_pipeline_operator_write($pipeline) && ! $this->isExplain;
+
+        // Explain does not use a cursor
+        if ($this->isExplain) {
             $options['useCursor'] = false;
+            unset($options['batchSize']);
+        }
+
+        /* Ignore batchSize for writes, since no documents are returned and a
+         * batchSize of zero could prevent the pipeline from executing. */
+        if ($this->isWrite) {
+            unset($options['batchSize']);
         }
 
         $this->databaseName = (string) $databaseName;
@@ -257,47 +259,30 @@ class Aggregate implements Executable, Explainable
      * @param Server $server
      * @return Traversable
      * @throws UnexpectedValueException if the command response was malformed
-     * @throws UnsupportedException if collation, read concern, or write concern is used and unsupported
+     * @throws UnsupportedException if read concern or write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['collation']) && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
-        if (isset($this->options['readConcern']) && ! server_supports_feature($server, self::$wireVersionForReadConcern)) {
-            throw UnsupportedException::readConcernNotSupported();
-        }
-
-        if (isset($this->options['writeConcern']) && ! server_supports_feature($server, self::$wireVersionForWriteConcern)) {
-            throw UnsupportedException::writeConcernNotSupported();
-        }
-
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
         if ($inTransaction) {
             if (isset($this->options['readConcern'])) {
                 throw UnsupportedException::readConcernNotSupportedInTransaction();
             }
+
             if (isset($this->options['writeConcern'])) {
                 throw UnsupportedException::writeConcernNotSupportedInTransaction();
             }
         }
 
-        $hasExplain = ! empty($this->options['explain']);
-        $hasWriteStage = $this->hasWriteStage();
-
         $command = new Command(
-            $this->createCommandDocument($server, $hasWriteStage),
+            $this->createCommandDocument(),
             $this->createCommandOptions()
         );
-        $options = $this->createOptions($hasWriteStage, $hasExplain);
 
-        $cursor = $hasWriteStage && ! $hasExplain
-            ? $server->executeReadWriteCommand($this->databaseName, $command, $options)
-            : $server->executeReadCommand($this->databaseName, $command, $options);
+        $cursor = $this->executeCommand($server, $command);
 
-        if ($this->options['useCursor'] || $hasExplain) {
+        if ($this->options['useCursor'] || $this->isExplain) {
             if (isset($this->options['typeMap'])) {
                 $cursor->setTypeMap($this->options['typeMap']);
             }
@@ -318,34 +303,40 @@ class Aggregate implements Executable, Explainable
         return new ArrayIterator($result->result);
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
-        return $this->createCommandDocument($server, $this->hasWriteStage());
+        return $this->createCommandDocument();
     }
 
-    private function createCommandDocument(Server $server, bool $hasWriteStage) : array
+    /**
+     * Create the aggregate command document.
+     *
+     * @return array
+     */
+    private function createCommandDocument()
     {
         $cmd = [
             'aggregate' => $this->collectionName ?? 1,
             'pipeline' => $this->pipeline,
         ];
 
-        $cmd['allowDiskUse'] = $this->options['allowDiskUse'];
-
-        if (! empty($this->options['bypassDocumentValidation']) &&
-            server_supports_feature($server, self::$wireVersionForDocumentLevelValidation)
-        ) {
-            $cmd['bypassDocumentValidation'] = $this->options['bypassDocumentValidation'];
-        }
-
-        foreach (['comment', 'explain', 'maxTimeMS'] as $option) {
+        foreach (['allowDiskUse', 'bypassDocumentValidation', 'comment', 'explain', 'maxTimeMS'] as $option) {
             if (isset($this->options[$option])) {
                 $cmd[$option] = $this->options[$option];
             }
         }
 
-        if (isset($this->options['collation'])) {
-            $cmd['collation'] = (object) $this->options['collation'];
+        foreach (['collation', 'let'] as $option) {
+            if (isset($this->options[$option])) {
+                $cmd[$option] = (object) $this->options[$option];
+            }
         }
 
         if (isset($this->options['hint'])) {
@@ -353,10 +344,7 @@ class Aggregate implements Executable, Explainable
         }
 
         if ($this->options['useCursor']) {
-            /* Ignore batchSize if pipeline includes an $out or $merge stage, as
-             * no documents will be returned and sending a batchSize of zero
-             * could prevent the pipeline from executing at all. */
-            $cmd['cursor'] = isset($this->options["batchSize"]) && ! $hasWriteStage
+            $cmd['cursor'] = isset($this->options["batchSize"])
                 ? ['batchSize' => $this->options["batchSize"]]
                 : new stdClass();
         }
@@ -364,7 +352,7 @@ class Aggregate implements Executable, Explainable
         return $cmd;
     }
 
-    private function createCommandOptions() : array
+    private function createCommandOptions(): array
     {
         $cmdOptions = [];
 
@@ -376,39 +364,38 @@ class Aggregate implements Executable, Explainable
     }
 
     /**
-     * Create options for executing the command.
+     * Execute the aggregate command using the appropriate Server method.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executereadcommand.php
-     * @see http://php.net/manual/en/mongodb-driver-server.executereadwritecommand.php
-     * @param boolean $hasWriteStage
-     * @param boolean $hasExplain
-     * @return array
+     * @see https://php.net/manual/en/mongodb-driver-server.executecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executereadcommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executereadwritecommand.php
      */
-    private function createOptions($hasWriteStage, $hasExplain)
+    private function executeCommand(Server $server, Command $command): Cursor
     {
         $options = [];
 
-        if (isset($this->options['readConcern'])) {
-            $options['readConcern'] = $this->options['readConcern'];
+        foreach (['readConcern', 'readPreference', 'session'] as $option) {
+            if (isset($this->options[$option])) {
+                $options[$option] = $this->options[$option];
+            }
         }
 
-        if (! $hasWriteStage && isset($this->options['readPreference'])) {
-            $options['readPreference'] = $this->options['readPreference'];
-        }
-
-        if (isset($this->options['session'])) {
-            $options['session'] = $this->options['session'];
-        }
-
-        if ($hasWriteStage && ! $hasExplain && isset($this->options['writeConcern'])) {
+        if ($this->isWrite && isset($this->options['writeConcern'])) {
             $options['writeConcern'] = $this->options['writeConcern'];
         }
 
-        return $options;
-    }
+        if (! $this->isWrite) {
+            return $server->executeReadCommand($this->databaseName, $command, $options);
+        }
 
-    private function hasWriteStage() : bool
-    {
-        return is_last_pipeline_operator_write($this->pipeline);
+        /* Server::executeReadWriteCommand() does not support a "readPreference"
+         * option, so fall back to executeCommand(). This means that libmongoc
+         * will not apply any client-level options (e.g. writeConcern), but that
+         * should not be an issue as PHPLIB handles inheritance on its own. */
+        if (isset($options['readPreference'])) {
+            return $server->executeCommand($this->databaseName, $command, $options);
+        }
+
+        return $server->executeReadWriteCommand($this->databaseName, $command, $options);
     }
 }

cache/stores/mongodb/MongoDB/Operation/BulkWrite.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -25,6 +25,7 @@ use MongoDB\Driver\Session;
 use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
+
 use function array_key_exists;
 use function count;
 use function current;
@@ -34,7 +35,6 @@ use function is_object;
 use function key;
 use function MongoDB\is_first_key_operator;
 use function MongoDB\is_pipeline;
-use function MongoDB\server_supports_feature;
 use function sprintf;
 
 /**
@@ -45,21 +45,12 @@ use function sprintf;
  */
 class BulkWrite implements Executable
 {
-    const DELETE_MANY = 'deleteMany';
-    const DELETE_ONE  = 'deleteOne';
-    const INSERT_ONE  = 'insertOne';
-    const REPLACE_ONE = 'replaceOne';
-    const UPDATE_MANY = 'updateMany';
-    const UPDATE_ONE  = 'updateOne';
-
-    /** @var integer */
-    private static $wireVersionForArrayFilters = 6;
-
-    /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var integer */
-    private static $wireVersionForDocumentLevelValidation = 4;
+    public const DELETE_MANY = 'deleteMany';
+    public const DELETE_ONE  = 'deleteOne';
+    public const INSERT_ONE  = 'insertOne';
+    public const REPLACE_ONE = 'replaceOne';
+    public const UPDATE_MANY = 'updateMany';
+    public const UPDATE_ONE  = 'updateOne';
 
     /** @var string */
     private $databaseName;
@@ -73,12 +64,6 @@ class BulkWrite implements Executable
     /** @var array */
     private $options;
 
-    /** @var boolean */
-    private $isArrayFiltersUsed = false;
-
-    /** @var boolean */
-    private $isCollationUsed = false;
-
     /**
      * Constructs a bulk write operation.
      *
@@ -101,16 +86,10 @@ class BulkWrite implements Executable
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
-     *
      * Supported options for replaceOne, updateMany, and updateOne operations:
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
-     *
      *  * upsert (boolean): When true, a new document is created if no document
      *    matches the query. The default is false.
      *
@@ -119,24 +98,26 @@ class BulkWrite implements Executable
      *  * arrayFilters (document array): A set of filters specifying to which
      *    array elements an update should apply.
      *
-     *    This is not supported for server versions < 3.6 and will result in an
-     *    exception at execution time if used.
-     *
      * Supported options for the bulk write operation:
      *
      *  * bypassDocumentValidation (boolean): If true, allows the write to
      *    circumvent document level validation. The default is false.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
+     *  * comment (mixed): BSON value to attach as a comment to this command(s)
+     *    associated with this bulk write.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * ordered (boolean): If true, when an insert fails, return without
      *    performing the remaining writes. If false, when a write fails,
      *    continue with the remaining writes, if any. The default is true.
      *
-     *  * session (MongoDB\Driver\Session): Client session.
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
      *
-     *    Sessions are not supported for server versions < 3.6.
+     *  * session (MongoDB\Driver\Session): Client session.
      *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
@@ -194,12 +175,8 @@ class BulkWrite implements Executable
 
                     $args[1]['limit'] = ($type === self::DELETE_ONE ? 1 : 0);
 
-                    if (isset($args[1]['collation'])) {
-                        $this->isCollationUsed = true;
-
-                        if (! is_array($args[1]['collation']) && ! is_object($args[1]['collation'])) {
-                            throw InvalidArgumentException::invalidType(sprintf('$operations[%d]["%s"][1]["collation"]', $i, $type), $args[1]['collation'], 'array or object');
-                        }
+                    if (isset($args[1]['collation']) && ! is_array($args[1]['collation']) && ! is_object($args[1]['collation'])) {
+                        throw InvalidArgumentException::invalidType(sprintf('$operations[%d]["%s"][1]["collation"]', $i, $type), $args[1]['collation'], 'array or object');
                     }
 
                     $operations[$i][$type][1] = $args[1];
@@ -230,12 +207,8 @@ class BulkWrite implements Executable
                     $args[2]['multi'] = false;
                     $args[2] += ['upsert' => false];
 
-                    if (isset($args[2]['collation'])) {
-                        $this->isCollationUsed = true;
-
-                        if (! is_array($args[2]['collation']) && ! is_object($args[2]['collation'])) {
-                            throw InvalidArgumentException::invalidType(sprintf('$operations[%d]["%s"][2]["collation"]', $i, $type), $args[2]['collation'], 'array or object');
-                        }
+                    if (isset($args[2]['collation']) && ! is_array($args[2]['collation']) && ! is_object($args[2]['collation'])) {
+                        throw InvalidArgumentException::invalidType(sprintf('$operations[%d]["%s"][2]["collation"]', $i, $type), $args[2]['collation'], 'array or object');
                     }
 
                     if (! is_bool($args[2]['upsert'])) {
@@ -271,20 +244,12 @@ class BulkWrite implements Executable
                     $args[2]['multi'] = ($type === self::UPDATE_MANY);
                     $args[2] += ['upsert' => false];
 
-                    if (isset($args[2]['arrayFilters'])) {
-                        $this->isArrayFiltersUsed = true;
-
-                        if (! is_array($args[2]['arrayFilters'])) {
-                            throw InvalidArgumentException::invalidType(sprintf('$operations[%d]["%s"][2]["arrayFilters"]', $i, $type), $args[2]['arrayFilters'], 'array');
-                        }
+                    if (isset($args[2]['arrayFilters']) && ! is_array($args[2]['arrayFilters'])) {
+                        throw InvalidArgumentException::invalidType(sprintf('$operations[%d]["%s"][2]["arrayFilters"]', $i, $type), $args[2]['arrayFilters'], 'array');
                     }
 
-                    if (isset($args[2]['collation'])) {
-                        $this->isCollationUsed = true;
-
-                        if (! is_array($args[2]['collation']) && ! is_object($args[2]['collation'])) {
-                            throw InvalidArgumentException::invalidType(sprintf('$operations[%d]["%s"][2]["collation"]', $i, $type), $args[2]['collation'], 'array or object');
-                        }
+                    if (isset($args[2]['collation']) && ! is_array($args[2]['collation']) && ! is_object($args[2]['collation'])) {
+                        throw InvalidArgumentException::invalidType(sprintf('$operations[%d]["%s"][2]["collation"]', $i, $type), $args[2]['collation'], 'array or object');
                     }
 
                     if (! is_bool($args[2]['upsert'])) {
@@ -320,6 +285,14 @@ class BulkWrite implements Executable
             throw InvalidArgumentException::invalidType('"writeConcern" option', $options['writeConcern'], WriteConcern::class);
         }
 
+        if (isset($options['let']) && ! is_array($options['let']) && ! is_object($options['let'])) {
+            throw InvalidArgumentException::invalidType('"let" option', $options['let'], 'array or object');
+        }
+
+        if (isset($options['bypassDocumentValidation']) && ! $options['bypassDocumentValidation']) {
+            unset($options['bypassDocumentValidation']);
+        }
+
         if (isset($options['writeConcern']) && $options['writeConcern']->isDefault()) {
             unset($options['writeConcern']);
         }
@@ -336,33 +309,17 @@ class BulkWrite implements Executable
      * @see Executable::execute()
      * @param Server $server
      * @return BulkWriteResult
-     * @throws UnsupportedException if array filters or collation is used and unsupported
+     * @throws UnsupportedException if write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if ($this->isArrayFiltersUsed && ! server_supports_feature($server, self::$wireVersionForArrayFilters)) {
-            throw UnsupportedException::arrayFiltersNotSupported();
-        }
-
-        if ($this->isCollationUsed && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
         if ($inTransaction && isset($this->options['writeConcern'])) {
             throw UnsupportedException::writeConcernNotSupportedInTransaction();
         }
 
-        $options = ['ordered' => $this->options['ordered']];
-
-        if (! empty($this->options['bypassDocumentValidation']) &&
-            server_supports_feature($server, self::$wireVersionForDocumentLevelValidation)
-        ) {
-            $options['bypassDocumentValidation'] = $this->options['bypassDocumentValidation'];
-        }
-
-        $bulk = new Bulk($options);
+        $bulk = new Bulk($this->createBulkWriteOptions());
         $insertedIds = [];
 
         foreach ($this->operations as $i => $operation) {
@@ -386,18 +343,41 @@ class BulkWrite implements Executable
             }
         }
 
-        $writeResult = $server->executeBulkWrite($this->databaseName . '.' . $this->collectionName, $bulk, $this->createOptions());
+        $writeResult = $server->executeBulkWrite($this->databaseName . '.' . $this->collectionName, $bulk, $this->createExecuteOptions());
 
         return new BulkWriteResult($writeResult, $insertedIds);
     }
 
     /**
-     * Create options for executing the bulk write.
+     * Create options for constructing the bulk write.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executebulkwrite.php
+     * @see https://php.net/manual/en/mongodb-driver-bulkwrite.construct.php
      * @return array
      */
-    private function createOptions()
+    private function createBulkWriteOptions()
+    {
+        $options = ['ordered' => $this->options['ordered']];
+
+        foreach (['bypassDocumentValidation', 'comment'] as $option) {
+            if (isset($this->options[$option])) {
+                $options[$option] = $this->options[$option];
+            }
+        }
+
+        if (isset($this->options['let'])) {
+            $options['let'] = (object) $this->options['let'];
+        }
+
+        return $options;
+    }
+
+    /**
+     * Create options for executing the bulk write.
+     *
+     * @see https://php.net/manual/en/mongodb-driver-server.executebulkwrite.php
+     * @return array
+     */
+    private function createExecuteOptions()
     {
         $options = [];
 

cache/stores/mongodb/MongoDB/Operation/Count.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -26,29 +26,23 @@ use MongoDB\Driver\Session;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnexpectedValueException;
 use MongoDB\Exception\UnsupportedException;
+
 use function current;
 use function is_array;
 use function is_float;
 use function is_integer;
 use function is_object;
 use function is_string;
-use function MongoDB\server_supports_feature;
 
 /**
  * Operation for the count command.
  *
  * @api
  * @see \MongoDB\Collection::count()
- * @see http://docs.mongodb.org/manual/reference/command/count/
+ * @see https://mongodb.com/docs/manual/reference/command/count/
  */
 class Count implements Executable, Explainable
 {
-    /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var integer */
-    private static $wireVersionForReadConcern = 4;
-
     /** @var string */
     private $databaseName;
 
@@ -68,8 +62,9 @@ class Count implements Executable, Explainable
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -82,15 +77,10 @@ class Count implements Executable, Explainable
      *
      *  * readConcern (MongoDB\Driver\ReadConcern): Read concern.
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
-     *
      *  * readPreference (MongoDB\Driver\ReadPreference): Read preference.
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * skip (integer): The number of documents to skip before returning the
      *    documents.
      *
@@ -155,19 +145,11 @@ class Count implements Executable, Explainable
      * @param Server $server
      * @return integer
      * @throws UnexpectedValueException if the command response was malformed
-     * @throws UnsupportedException if collation or read concern is used and unsupported
+     * @throws UnsupportedException if read concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['collation']) && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
-        if (isset($this->options['readConcern']) && ! server_supports_feature($server, self::$wireVersionForReadConcern)) {
-            throw UnsupportedException::readConcernNotSupported();
-        }
-
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
         if ($inTransaction && isset($this->options['readConcern'])) {
             throw UnsupportedException::readConcernNotSupportedInTransaction();
@@ -184,6 +166,13 @@ class Count implements Executable, Explainable
         return (integer) $result->n;
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->createCommandDocument();
@@ -210,7 +199,7 @@ class Count implements Executable, Explainable
             $cmd['hint'] = is_array($this->options['hint']) ? (object) $this->options['hint'] : $this->options['hint'];
         }
 
-        foreach (['limit', 'maxTimeMS', 'skip'] as $option) {
+        foreach (['comment', 'limit', 'maxTimeMS', 'skip'] as $option) {
             if (isset($this->options[$option])) {
                 $cmd[$option] = $this->options[$option];
             }
@@ -222,7 +211,7 @@ class Count implements Executable, Explainable
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executereadcommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executereadcommand.php
      * @return array
      */
     private function createOptions()

cache/stores/mongodb/MongoDB/Operation/CountDocuments.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -22,6 +22,7 @@ use MongoDB\Driver\Server;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnexpectedValueException;
 use MongoDB\Exception\UnsupportedException;
+
 use function array_intersect_key;
 use function count;
 use function current;
@@ -64,8 +65,9 @@ class CountDocuments implements Executable
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    Only string values are supported for server versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -78,15 +80,10 @@ class CountDocuments implements Executable
      *
      *  * readConcern (MongoDB\Driver\ReadConcern): Read concern.
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
-     *
      *  * readPreference (MongoDB\Driver\ReadPreference): Read preference.
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * skip (integer): The number of documents to skip before returning the
      *    documents.
      *
@@ -114,7 +111,7 @@ class CountDocuments implements Executable
         $this->collectionName = (string) $collectionName;
         $this->filter = $filter;
 
-        $this->aggregateOptions = array_intersect_key($options, ['collation' => 1, 'hint' => 1, 'maxTimeMS' => 1, 'readConcern' => 1, 'readPreference' => 1, 'session' => 1]);
+        $this->aggregateOptions = array_intersect_key($options, ['collation' => 1, 'comment' => 1, 'hint' => 1, 'maxTimeMS' => 1, 'readConcern' => 1, 'readPreference' => 1, 'session' => 1]);
         $this->countOptions = array_intersect_key($options, ['limit' => 1, 'skip' => 1]);
 
         $this->aggregate = $this->createAggregate();

cache/stores/mongodb/MongoDB/Operation/CreateCollection.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -23,15 +23,16 @@ use MongoDB\Driver\Server;
 use MongoDB\Driver\Session;
 use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
-use MongoDB\Exception\UnsupportedException;
+
 use function current;
 use function is_array;
 use function is_bool;
 use function is_integer;
 use function is_object;
 use function is_string;
-use function MongoDB\server_supports_feature;
+use function sprintf;
 use function trigger_error;
+
 use const E_USER_DEPRECATED;
 
 /**
@@ -39,18 +40,12 @@ use const E_USER_DEPRECATED;
  *
  * @api
  * @see \MongoDB\Database::createCollection()
- * @see http://docs.mongodb.org/manual/reference/command/create/
+ * @see https://mongodb.com/docs/manual/reference/command/create/
  */
 class CreateCollection implements Executable
 {
-    const USE_POWER_OF_2_SIZES = 1;
-    const NO_PADDING = 2;
-
-    /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var integer */
-    private static $wireVersionForWriteConcern = 5;
+    public const USE_POWER_OF_2_SIZES = 1;
+    public const NO_PADDING = 2;
 
     /** @var string */
     private $databaseName;
@@ -77,10 +72,26 @@ class CreateCollection implements Executable
      *  * capped (boolean): Specify true to create a capped collection. If set,
      *    the size option must also be specified. The default is false.
      *
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
+     *
+     *  * changeStreamPreAndPostImages (document): Used to configure support for
+     *    pre- and post-images in change streams.
+     *
+     *    This is not supported for server versions < 6.0.
+     *
+     *  * clusteredIndex (document): A clustered index specification.
+     *
+     *    This is not supported for server versions < 5.3.
+     *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * encryptedFields (document): CSFLE specification.
+     *
+     *  * expireAfterSeconds: The TTL for documents in time series collections.
+     *
+     *    This is not supported for servers versions < 5.0.
      *
      *  * flags (integer): Options for the MMAPv1 storage engine only. Must be a
      *    bitwise combination CreateCollection::USE_POWER_OF_2_SIZES and
@@ -96,14 +107,20 @@ class CreateCollection implements Executable
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
      *    run.
      *
-     *  * session (MongoDB\Driver\Session): Client session.
+     *  * pipeline (array): An array that consists of the aggregation pipeline
+     *    stage(s), which will be applied to the collection or view specified by
+     *    viewOn.
      *
-     *    Sessions are not supported for server versions < 3.6.
+     *  * session (MongoDB\Driver\Session): Client session.
      *
      *  * size (integer): The maximum number of bytes for a capped collection.
      *
      *  * storageEngine (document): Storage engine options.
      *
+     *  * timeseries (document): Options for time series collections.
+     *
+     *    This is not supported for servers versions < 5.0.
+     *
      *  * typeMap (array): Type map for BSON deserialization. This will only be
      *    used for the returned command result document.
      *
@@ -113,13 +130,13 @@ class CreateCollection implements Executable
      *
      *  * validator (document): Validation rules or expressions.
      *
+     *  * viewOn (string): The name of the source collection or view from which
+     *    to create the view.
+     *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
-     *
-     * @see http://source.wiredtiger.com/2.4.1/struct_w_t___s_e_s_s_i_o_n.html#a358ca4141d59c345f401c58501276bbb
-     * @see https://docs.mongodb.org/manual/core/document-validation/
+     * @see https://source.wiredtiger.com/2.4.1/struct_w_t___s_e_s_s_i_o_n.html#a358ca4141d59c345f401c58501276bbb
+     * @see https://mongodb.com/docs/manual/core/schema-validation/
      * @param string $databaseName   Database name
      * @param string $collectionName Collection name
      * @param array  $options        Command options
@@ -135,10 +152,26 @@ class CreateCollection implements Executable
             throw InvalidArgumentException::invalidType('"capped" option', $options['capped'], 'boolean');
         }
 
+        if (isset($options['changeStreamPreAndPostImages']) && ! is_array($options['changeStreamPreAndPostImages']) && ! is_object($options['changeStreamPreAndPostImages'])) {
+            throw InvalidArgumentException::invalidType('"changeStreamPreAndPostImages" option', $options['changeStreamPreAndPostImages'], 'array or object');
+        }
+
+        if (isset($options['clusteredIndex']) && ! is_array($options['clusteredIndex']) && ! is_object($options['clusteredIndex'])) {
+            throw InvalidArgumentException::invalidType('"clusteredIndex" option', $options['clusteredIndex'], 'array or object');
+        }
+
         if (isset($options['collation']) && ! is_array($options['collation']) && ! is_object($options['collation'])) {
             throw InvalidArgumentException::invalidType('"collation" option', $options['collation'], 'array or object');
         }
 
+        if (isset($options['encryptedFields']) && ! is_array($options['encryptedFields']) && ! is_object($options['encryptedFields'])) {
+            throw InvalidArgumentException::invalidType('"encryptedFields" option', $options['encryptedFields'], 'array or object');
+        }
+
+        if (isset($options['expireAfterSeconds']) && ! is_integer($options['expireAfterSeconds'])) {
+            throw InvalidArgumentException::invalidType('"expireAfterSeconds" option', $options['expireAfterSeconds'], 'integer');
+        }
+
         if (isset($options['flags']) && ! is_integer($options['flags'])) {
             throw InvalidArgumentException::invalidType('"flags" option', $options['flags'], 'integer');
         }
@@ -155,6 +188,10 @@ class CreateCollection implements Executable
             throw InvalidArgumentException::invalidType('"maxTimeMS" option', $options['maxTimeMS'], 'integer');
         }
 
+        if (isset($options['pipeline']) && ! is_array($options['pipeline'])) {
+            throw InvalidArgumentException::invalidType('"pipeline" option', $options['pipeline'], 'array');
+        }
+
         if (isset($options['session']) && ! $options['session'] instanceof Session) {
             throw InvalidArgumentException::invalidType('"session" option', $options['session'], Session::class);
         }
@@ -167,6 +204,10 @@ class CreateCollection implements Executable
             throw InvalidArgumentException::invalidType('"storageEngine" option', $options['storageEngine'], 'array or object');
         }
 
+        if (isset($options['timeseries']) && ! is_array($options['timeseries']) && ! is_object($options['timeseries'])) {
+            throw InvalidArgumentException::invalidType('"timeseries" option', $options['timeseries'], ['array', 'object']);
+        }
+
         if (isset($options['typeMap']) && ! is_array($options['typeMap'])) {
             throw InvalidArgumentException::invalidType('"typeMap" option', $options['typeMap'], 'array');
         }
@@ -183,6 +224,10 @@ class CreateCollection implements Executable
             throw InvalidArgumentException::invalidType('"validator" option', $options['validator'], 'array or object');
         }
 
+        if (isset($options['viewOn']) && ! is_string($options['viewOn'])) {
+            throw InvalidArgumentException::invalidType('"viewOn" option', $options['viewOn'], 'string');
+        }
+
         if (isset($options['writeConcern']) && ! $options['writeConcern'] instanceof WriteConcern) {
             throw InvalidArgumentException::invalidType('"writeConcern" option', $options['writeConcern'], WriteConcern::class);
         }
@@ -195,6 +240,22 @@ class CreateCollection implements Executable
             trigger_error('The "autoIndexId" option is deprecated and will be removed in a future release', E_USER_DEPRECATED);
         }
 
+        if (isset($options['pipeline'])) {
+            $expectedIndex = 0;
+
+            foreach ($options['pipeline'] as $i => $operation) {
+                if ($i !== $expectedIndex) {
+                    throw new InvalidArgumentException(sprintf('The "pipeline" option is not a list (unexpected index: "%s")', $i));
+                }
+
+                if (! is_array($operation) && ! is_object($operation)) {
+                    throw InvalidArgumentException::invalidType(sprintf('$options["pipeline"][%d]', $i), $operation, 'array or object');
+                }
+
+                $expectedIndex += 1;
+            }
+        }
+
         $this->databaseName = (string) $databaseName;
         $this->collectionName = (string) $collectionName;
         $this->options = $options;
@@ -206,19 +267,10 @@ class CreateCollection implements Executable
      * @see Executable::execute()
      * @param Server $server
      * @return array|object Command result document
-     * @throws UnsupportedException if collation or write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['collation']) && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
-        if (isset($this->options['writeConcern']) && ! server_supports_feature($server, self::$wireVersionForWriteConcern)) {
-            throw UnsupportedException::writeConcernNotSupported();
-        }
-
         $cursor = $server->executeWriteCommand($this->databaseName, $this->createCommand(), $this->createOptions());
 
         if (isset($this->options['typeMap'])) {
@@ -237,13 +289,13 @@ class CreateCollection implements Executable
     {
         $cmd = ['create' => $this->collectionName];
 
-        foreach (['autoIndexId', 'capped', 'flags', 'max', 'maxTimeMS', 'size', 'validationAction', 'validationLevel'] as $option) {
+        foreach (['autoIndexId', 'capped', 'comment', 'expireAfterSeconds', 'flags', 'max', 'maxTimeMS', 'pipeline', 'size', 'validationAction', 'validationLevel', 'viewOn'] as $option) {
             if (isset($this->options[$option])) {
                 $cmd[$option] = $this->options[$option];
             }
         }
 
-        foreach (['collation', 'indexOptionDefaults', 'storageEngine', 'validator'] as $option) {
+        foreach (['changeStreamPreAndPostImages', 'clusteredIndex', 'collation', 'encryptedFields', 'indexOptionDefaults', 'storageEngine', 'timeseries', 'validator'] as $option) {
             if (isset($this->options[$option])) {
                 $cmd[$option] = (object) $this->options[$option];
             }
@@ -255,7 +307,7 @@ class CreateCollection implements Executable
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executewritecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executewritecommand.php
      * @return array
      */
     private function createOptions()

cache/stores/mongodb/MongoDB/Operation/CreateIndexes.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -25,6 +25,7 @@ use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
 use MongoDB\Model\IndexInput;
+
 use function array_map;
 use function is_array;
 use function is_integer;
@@ -38,16 +39,10 @@ use function sprintf;
  * @api
  * @see \MongoDB\Collection::createIndex()
  * @see \MongoDB\Collection::createIndexes()
- * @see http://docs.mongodb.org/manual/reference/command/createIndexes/
+ * @see https://mongodb.com/docs/manual/reference/command/createIndexes/
  */
 class CreateIndexes implements Executable
 {
-    /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var integer */
-    private static $wireVersionForWriteConcern = 5;
-
     /** @var integer */
     private static $wireVersionForCommitQuorum = 9;
 
@@ -60,9 +55,6 @@ class CreateIndexes implements Executable
     /** @var array */
     private $indexes = [];
 
-    /** @var boolean */
-    private $isCollationUsed = false;
-
     /** @var array */
     private $options = [];
 
@@ -71,6 +63,10 @@ class CreateIndexes implements Executable
      *
      * Supported options:
      *
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
+     *
      *  * commitQuorum (integer|string): Specifies how many data-bearing members
      *    of a replica set, including the primary, must complete the index
      *    builds successfully before the primary marks the indexes as ready.
@@ -80,13 +76,8 @@ class CreateIndexes implements Executable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
-     *
      * @param string  $databaseName   Database name
      * @param string  $collectionName Collection name
      * @param array[] $indexes        List of index specifications
@@ -110,10 +101,6 @@ class CreateIndexes implements Executable
                 throw InvalidArgumentException::invalidType(sprintf('$index[%d]', $i), $index, 'array');
             }
 
-            if (isset($index['collation'])) {
-                $this->isCollationUsed = true;
-            }
-
             $this->indexes[] = new IndexInput($index);
 
             $expectedIndex += 1;
@@ -150,19 +137,11 @@ class CreateIndexes implements Executable
      * @see Executable::execute()
      * @param Server $server
      * @return string[] The names of the created indexes
-     * @throws UnsupportedException if collation or write concern is used and unsupported
+     * @throws UnsupportedException if write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if ($this->isCollationUsed && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
-        if (isset($this->options['writeConcern']) && ! server_supports_feature($server, self::$wireVersionForWriteConcern)) {
-            throw UnsupportedException::writeConcernNotSupported();
-        }
-
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
         if ($inTransaction && isset($this->options['writeConcern'])) {
             throw UnsupportedException::writeConcernNotSupportedInTransaction();
@@ -178,7 +157,7 @@ class CreateIndexes implements Executable
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executewritecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executewritecommand.php
      * @return array
      */
     private function createOptions()
@@ -220,8 +199,10 @@ class CreateIndexes implements Executable
             $cmd['commitQuorum'] = $this->options['commitQuorum'];
         }
 
-        if (isset($this->options['maxTimeMS'])) {
-            $cmd['maxTimeMS'] = $this->options['maxTimeMS'];
+        foreach (['comment', 'maxTimeMS'] as $option) {
+            if (isset($this->options[$option])) {
+                $cmd[$option] = $this->options[$option];
+            }
         }
 
         $server->executeWriteCommand($this->databaseName, new Command($cmd), $this->createOptions());

cache/stores/mongodb/MongoDB/Operation/DatabaseCommand.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -23,6 +23,7 @@ use MongoDB\Driver\ReadPreference;
 use MongoDB\Driver\Server;
 use MongoDB\Driver\Session;
 use MongoDB\Exception\InvalidArgumentException;
+
 use function is_array;
 use function is_object;
 
@@ -56,8 +57,6 @@ class DatabaseCommand implements Executable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * typeMap (array): Type map for BSON deserialization. This will be
      *    applied to the returned Cursor (it is not sent to the server).
      *
@@ -110,7 +109,7 @@ class DatabaseCommand implements Executable
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executecommand.php
      * @return array
      */
     private function createOptions()

cache/stores/mongodb/MongoDB/Operation/Delete.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -25,9 +25,11 @@ use MongoDB\Driver\Session;
 use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
+
 use function is_array;
 use function is_object;
 use function is_string;
+use function MongoDB\is_write_concern_acknowledged;
 use function MongoDB\server_supports_feature;
 
 /**
@@ -37,15 +39,12 @@ use function MongoDB\server_supports_feature;
  * classes.
  *
  * @internal
- * @see http://docs.mongodb.org/manual/reference/command/delete/
+ * @see https://mongodb.com/docs/manual/reference/command/delete/
  */
 class Delete implements Executable, Explainable
 {
     /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var int */
-    private static $wireVersionForHintServerSideError = 5;
+    private static $wireVersionForHint = 9;
 
     /** @var string */
     private $databaseName;
@@ -69,8 +68,9 @@ class Delete implements Executable, Explainable
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -79,9 +79,12 @@ class Delete implements Executable, Explainable
      *    This is not supported for server versions < 4.4 and will result in an
      *    exception at execution time if used.
      *
-     *  * session (MongoDB\Driver\Session): Client session.
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
      *
-     *    Sessions are not supported for server versions < 3.6.
+     *  * session (MongoDB\Driver\Session): Client session.
      *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
@@ -120,6 +123,10 @@ class Delete implements Executable, Explainable
             throw InvalidArgumentException::invalidType('"writeConcern" option', $options['writeConcern'], WriteConcern::class);
         }
 
+        if (isset($options['let']) && ! is_array($options['let']) && ! is_object($options['let'])) {
+            throw InvalidArgumentException::invalidType('"let" option', $options['let'], 'array or object');
+        }
+
         if (isset($options['writeConcern']) && $options['writeConcern']->isDefault()) {
             unset($options['writeConcern']);
         }
@@ -137,18 +144,17 @@ class Delete implements Executable, Explainable
      * @see Executable::execute()
      * @param Server $server
      * @return DeleteResult
+     * @throws UnsupportedException if hint or write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['collation']) && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
-        /* Server versions >= 3.4.0 raise errors for unknown update
-         * options. For previous versions, the CRUD spec requires a client-side
-         * error. */
-        if (isset($this->options['hint']) && ! server_supports_feature($server, self::$wireVersionForHintServerSideError)) {
+        /* CRUD spec requires a client-side error when using "hint" with an
+         * unacknowledged write concern on an unsupported server. */
+        if (
+            isset($this->options['writeConcern']) && ! is_write_concern_acknowledged($this->options['writeConcern']) &&
+            isset($this->options['hint']) && ! server_supports_feature($server, self::$wireVersionForHint)
+        ) {
             throw UnsupportedException::hintNotSupported();
         }
 
@@ -157,7 +163,7 @@ class Delete implements Executable, Explainable
             throw UnsupportedException::writeConcernNotSupportedInTransaction();
         }
 
-        $bulk = new Bulk();
+        $bulk = new Bulk($this->createBulkWriteOptions());
         $bulk->delete($this->filter, $this->createDeleteOptions());
 
         $writeResult = $server->executeBulkWrite($this->databaseName . '.' . $this->collectionName, $bulk, $this->createExecuteOptions());
@@ -165,6 +171,13 @@ class Delete implements Executable, Explainable
         return new DeleteResult($writeResult);
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         $cmd = ['delete' => $this->collectionName, 'deletes' => [['q' => $this->filter] + $this->createDeleteOptions()]];
@@ -176,6 +189,26 @@ class Delete implements Executable, Explainable
         return $cmd;
     }
 
+    /**
+     * Create options for constructing the bulk write.
+     *
+     * @see https://php.net/manual/en/mongodb-driver-bulkwrite.construct.php
+     */
+    private function createBulkWriteOptions(): array
+    {
+        $options = [];
+
+        if (isset($this->options['comment'])) {
+            $options['comment'] = $this->options['comment'];
+        }
+
+        if (isset($this->options['let'])) {
+            $options['let'] = (object) $this->options['let'];
+        }
+
+        return $options;
+    }
+
     /**
      * Create options for the delete command.
      *
@@ -202,7 +235,7 @@ class Delete implements Executable, Explainable
     /**
      * Create options for executing the bulk write.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executebulkwrite.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executebulkwrite.php
      * @return array
      */
     private function createExecuteOptions()

cache/stores/mongodb/MongoDB/Operation/DeleteMany.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -28,7 +28,7 @@ use MongoDB\Exception\UnsupportedException;
  *
  * @api
  * @see \MongoDB\Collection::deleteOne()
- * @see http://docs.mongodb.org/manual/reference/command/delete/
+ * @see https://mongodb.com/docs/manual/reference/command/delete/
  */
 class DeleteMany implements Executable, Explainable
 {
@@ -42,8 +42,9 @@ class DeleteMany implements Executable, Explainable
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -52,9 +53,12 @@ class DeleteMany implements Executable, Explainable
      *    This is not supported for server versions < 4.4 and will result in an
      *    exception at execution time if used.
      *
-     *  * session (MongoDB\Driver\Session): Client session.
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
      *
-     *    Sessions are not supported for server versions < 3.6.
+     *  * session (MongoDB\Driver\Session): Client session.
      *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
@@ -83,6 +87,13 @@ class DeleteMany implements Executable, Explainable
         return $this->delete->execute($server);
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->delete->getCommandDocument($server);

cache/stores/mongodb/MongoDB/Operation/DeleteOne.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -28,7 +28,7 @@ use MongoDB\Exception\UnsupportedException;
  *
  * @api
  * @see \MongoDB\Collection::deleteOne()
- * @see http://docs.mongodb.org/manual/reference/command/delete/
+ * @see https://mongodb.com/docs/manual/reference/command/delete/
  */
 class DeleteOne implements Executable, Explainable
 {
@@ -42,8 +42,9 @@ class DeleteOne implements Executable, Explainable
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -52,9 +53,12 @@ class DeleteOne implements Executable, Explainable
      *    This is not supported for server versions < 4.4 and will result in an
      *    exception at execution time if used.
      *
-     *  * session (MongoDB\Driver\Session): Client session.
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
      *
-     *    Sessions are not supported for server versions < 3.6.
+     *  * session (MongoDB\Driver\Session): Client session.
      *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
@@ -83,6 +87,13 @@ class DeleteOne implements Executable, Explainable
         return $this->delete->execute($server);
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->delete->getCommandDocument($server);

cache/stores/mongodb/MongoDB/Operation/Distinct.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -26,28 +26,22 @@ use MongoDB\Driver\Session;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnexpectedValueException;
 use MongoDB\Exception\UnsupportedException;
+
 use function current;
 use function is_array;
 use function is_integer;
 use function is_object;
 use function MongoDB\create_field_path_type_map;
-use function MongoDB\server_supports_feature;
 
 /**
  * Operation for the distinct command.
  *
  * @api
  * @see \MongoDB\Collection::distinct()
- * @see http://docs.mongodb.org/manual/reference/command/distinct/
+ * @see https://mongodb.com/docs/manual/reference/command/distinct/
  */
 class Distinct implements Executable, Explainable
 {
-    /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var integer */
-    private static $wireVersionForReadConcern = 4;
-
     /** @var string */
     private $databaseName;
 
@@ -70,23 +64,19 @@ class Distinct implements Executable, Explainable
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
      *    run.
      *
      *  * readConcern (MongoDB\Driver\ReadConcern): Read concern.
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
-     *
      *  * readPreference (MongoDB\Driver\ReadPreference): Read preference.
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * typeMap (array): Type map for BSON deserialization.
      *
      * @param string       $databaseName   Database name
@@ -144,19 +134,11 @@ class Distinct implements Executable, Explainable
      * @param Server $server
      * @return mixed[]
      * @throws UnexpectedValueException if the command response was malformed
-     * @throws UnsupportedException if collation or read concern is used and unsupported
+     * @throws UnsupportedException if read concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['collation']) && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
-        if (isset($this->options['readConcern']) && ! server_supports_feature($server, self::$wireVersionForReadConcern)) {
-            throw UnsupportedException::readConcernNotSupported();
-        }
-
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
         if ($inTransaction && isset($this->options['readConcern'])) {
             throw UnsupportedException::readConcernNotSupportedInTransaction();
@@ -177,6 +159,13 @@ class Distinct implements Executable, Explainable
         return $result->values;
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->createCommandDocument();
@@ -202,8 +191,10 @@ class Distinct implements Executable, Explainable
             $cmd['collation'] = (object) $this->options['collation'];
         }
 
-        if (isset($this->options['maxTimeMS'])) {
-            $cmd['maxTimeMS'] = $this->options['maxTimeMS'];
+        foreach (['comment', 'maxTimeMS'] as $option) {
+            if (isset($this->options[$option])) {
+                $cmd[$option] = $this->options[$option];
+            }
         }
 
         return $cmd;
@@ -212,7 +203,7 @@ class Distinct implements Executable, Explainable
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executereadcommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executereadcommand.php
      * @return array
      */
     private function createOptions()

cache/stores/mongodb/MongoDB/Operation/DropCollection.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -24,9 +24,9 @@ use MongoDB\Driver\Session;
 use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
+
 use function current;
 use function is_array;
-use function MongoDB\server_supports_feature;
 
 /**
  * Operation for the drop command.
@@ -34,19 +34,13 @@ use function MongoDB\server_supports_feature;
  * @api
  * @see \MongoDB\Collection::drop()
  * @see \MongoDB\Database::dropCollection()
- * @see http://docs.mongodb.org/manual/reference/command/drop/
+ * @see https://mongodb.com/docs/manual/reference/command/drop/
  */
 class DropCollection implements Executable
 {
     /** @var integer */
     private static $errorCodeNamespaceNotFound = 26;
 
-    /** @var string */
-    private static $errorMessageNamespaceNotFound = 'ns not found';
-
-    /** @var integer */
-    private static $wireVersionForWriteConcern = 5;
-
     /** @var string */
     private $databaseName;
 
@@ -61,18 +55,17 @@ class DropCollection implements Executable
      *
      * Supported options:
      *
-     *  * session (MongoDB\Driver\Session): Client session.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
      *
-     *    Sessions are not supported for server versions < 3.6.
+     *    This is not supported for servers versions < 4.4.
+     *
+     *  * session (MongoDB\Driver\Session): Client session.
      *
      *  * typeMap (array): Type map for BSON deserialization. This will be used
      *    for the returned command result document.
      *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
-     *
      * @param string $databaseName   Database name
      * @param string $collectionName Collection name
      * @param array  $options        Command options
@@ -107,30 +100,23 @@ class DropCollection implements Executable
      * @see Executable::execute()
      * @param Server $server
      * @return array|object Command result document
-     * @throws UnsupportedException if writeConcern is used and unsupported
+     * @throws UnsupportedException if write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['writeConcern']) && ! server_supports_feature($server, self::$wireVersionForWriteConcern)) {
-            throw UnsupportedException::writeConcernNotSupported();
-        }
-
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
         if ($inTransaction && isset($this->options['writeConcern'])) {
             throw UnsupportedException::writeConcernNotSupportedInTransaction();
         }
 
-        $command = new Command(['drop' => $this->collectionName]);
-
         try {
-            $cursor = $server->executeWriteCommand($this->databaseName, $command, $this->createOptions());
+            $cursor = $server->executeWriteCommand($this->databaseName, $this->createCommand(), $this->createOptions());
         } catch (CommandException $e) {
             /* The server may return an error if the collection does not exist.
-             * Check for an error code (or message for pre-3.2 servers) and
-             * return the command reply instead of throwing. */
-            if ($e->getCode() === self::$errorCodeNamespaceNotFound ||
-                $e->getMessage() === self::$errorMessageNamespaceNotFound) {
+             * Check for an error code and return the command reply instead of
+             * throwing. */
+            if ($e->getCode() === self::$errorCodeNamespaceNotFound) {
                 return $e->getResultDocument();
             }
 
@@ -144,10 +130,26 @@ class DropCollection implements Executable
         return current($cursor->toArray());
     }
 
+    /**
+     * Create the drop command.
+     *
+     * @return Command
+     */
+    private function createCommand()
+    {
+        $cmd = ['drop' => $this->collectionName];
+
+        if (isset($this->options['comment'])) {
+            $cmd['comment'] = $this->options['comment'];
+        }
+
+        return new Command($cmd);
+    }
+
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executewritecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executewritecommand.php
      * @return array
      */
     private function createOptions()

cache/stores/mongodb/MongoDB/Operation/DropDatabase.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -23,10 +23,9 @@ use MongoDB\Driver\Server;
 use MongoDB\Driver\Session;
 use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
-use MongoDB\Exception\UnsupportedException;
+
 use function current;
 use function is_array;
-use function MongoDB\server_supports_feature;
 
 /**
  * Operation for the dropDatabase command.
@@ -34,13 +33,10 @@ use function MongoDB\server_supports_feature;
  * @api
  * @see \MongoDB\Client::dropDatabase()
  * @see \MongoDB\Database::drop()
- * @see http://docs.mongodb.org/manual/reference/command/dropDatabase/
+ * @see https://mongodb.com/docs/manual/reference/command/dropDatabase/
  */
 class DropDatabase implements Executable
 {
-    /** @var integer */
-    private static $wireVersionForWriteConcern = 5;
-
     /** @var string */
     private $databaseName;
 
@@ -52,18 +48,17 @@ class DropDatabase implements Executable
      *
      * Supported options:
      *
-     *  * session (MongoDB\Driver\Session): Client session.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
      *
-     *    Sessions are not supported for server versions < 3.6.
+     *    This is not supported for servers versions < 4.4.
+     *
+     *  * session (MongoDB\Driver\Session): Client session.
      *
      *  * typeMap (array): Type map for BSON deserialization. This will be used
      *    for the returned command result document.
      *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
-     *
      * @param string $databaseName Database name
      * @param array  $options      Command options
      * @throws InvalidArgumentException for parameter/option parsing errors
@@ -96,17 +91,11 @@ class DropDatabase implements Executable
      * @see Executable::execute()
      * @param Server $server
      * @return array|object Command result document
-     * @throws UnsupportedException if writeConcern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['writeConcern']) && ! server_supports_feature($server, self::$wireVersionForWriteConcern)) {
-            throw UnsupportedException::writeConcernNotSupported();
-        }
-
-        $command = new Command(['dropDatabase' => 1]);
-        $cursor = $server->executeWriteCommand($this->databaseName, $command, $this->createOptions());
+        $cursor = $server->executeWriteCommand($this->databaseName, $this->createCommand(), $this->createOptions());
 
         if (isset($this->options['typeMap'])) {
             $cursor->setTypeMap($this->options['typeMap']);
@@ -115,10 +104,26 @@ class DropDatabase implements Executable
         return current($cursor->toArray());
     }
 
+    /**
+     * Create the dropDatabase command.
+     *
+     * @return Command
+     */
+    private function createCommand()
+    {
+        $cmd = ['dropDatabase' => 1];
+
+        if (isset($this->options['comment'])) {
+            $cmd['comment'] = $this->options['comment'];
+        }
+
+        return new Command($cmd);
+    }
+
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executewritecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executewritecommand.php
      * @return array
      */
     private function createOptions()

cache/stores/mongodb/MongoDB/Operation/DropIndexes.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -24,23 +24,20 @@ use MongoDB\Driver\Session;
 use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
+
 use function current;
 use function is_array;
 use function is_integer;
-use function MongoDB\server_supports_feature;
 
 /**
  * Operation for the dropIndexes command.
  *
  * @api
  * @see \MongoDB\Collection::dropIndexes()
- * @see http://docs.mongodb.org/manual/reference/command/dropIndexes/
+ * @see https://mongodb.com/docs/manual/reference/command/dropIndexes/
  */
 class DropIndexes implements Executable
 {
-    /** @var integer */
-    private static $wireVersionForWriteConcern = 5;
-
     /** @var string */
     private $databaseName;
 
@@ -58,21 +55,20 @@ class DropIndexes implements Executable
      *
      * Supported options:
      *
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
+     *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
      *    run.
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * typeMap (array): Type map for BSON deserialization. This will be used
      *    for the returned command result document.
      *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
-     *
      * @param string $databaseName   Database name
      * @param string $collectionName Collection name
      * @param string $indexName      Index name (use "*" to drop all indexes)
@@ -119,15 +115,11 @@ class DropIndexes implements Executable
      * @see Executable::execute()
      * @param Server $server
      * @return array|object Command result document
-     * @throws UnsupportedException if writeConcern is used and unsupported
+     * @throws UnsupportedException if write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['writeConcern']) && ! server_supports_feature($server, self::$wireVersionForWriteConcern)) {
-            throw UnsupportedException::writeConcernNotSupported();
-        }
-
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
         if ($inTransaction && isset($this->options['writeConcern'])) {
             throw UnsupportedException::writeConcernNotSupportedInTransaction();
@@ -154,8 +146,10 @@ class DropIndexes implements Executable
             'index' => $this->indexName,
         ];
 
-        if (isset($this->options['maxTimeMS'])) {
-            $cmd['maxTimeMS'] = $this->options['maxTimeMS'];
+        foreach (['comment', 'maxTimeMS'] as $option) {
+            if (isset($this->options[$option])) {
+                $cmd[$option] = $this->options[$option];
+            }
         }
 
         return new Command($cmd);
@@ -164,7 +158,7 @@ class DropIndexes implements Executable
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executewritecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executewritecommand.php
      * @return array
      */
     private function createOptions()

cache/stores/mongodb/MongoDB/Operation/EstimatedDocumentCount.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,18 +18,23 @@
 namespace MongoDB\Operation;
 
 use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
+use MongoDB\Driver\ReadConcern;
+use MongoDB\Driver\ReadPreference;
 use MongoDB\Driver\Server;
+use MongoDB\Driver\Session;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnexpectedValueException;
 use MongoDB\Exception\UnsupportedException;
+
 use function array_intersect_key;
+use function is_integer;
 
 /**
  * Operation for obtaining an estimated count of documents in a collection
  *
  * @api
  * @see \MongoDB\Collection::estimatedDocumentCount()
- * @see http://docs.mongodb.org/manual/reference/command/count/
+ * @see https://mongodb.com/docs/manual/reference/command/count/
  */
 class EstimatedDocumentCount implements Executable, Explainable
 {
@@ -42,28 +47,31 @@ class EstimatedDocumentCount implements Executable, Explainable
     /** @var array */
     private $options;
 
-    /** @var Count */
-    private $count;
+    /** @var int */
+    private static $errorCodeCollectionNotFound = 26;
+
+    /** @var int */
+    private static $wireVersionForCollStats = 12;
 
     /**
-     * Constructs a count command.
+     * Constructs a command to get the estimated number of documents in a
+     * collection.
      *
      * Supported options:
      *
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
+     *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
      *    run.
      *
      *  * readConcern (MongoDB\Driver\ReadConcern): Read concern.
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
-     *
      *  * readPreference (MongoDB\Driver\ReadPreference): Read preference.
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      * @param string $databaseName   Database name
      * @param string $collectionName Collection name
      * @param array  $options        Command options
@@ -73,9 +81,24 @@ class EstimatedDocumentCount implements Executable, Explainable
     {
         $this->databaseName = (string) $databaseName;
         $this->collectionName = (string) $collectionName;
-        $this->options = array_intersect_key($options, ['maxTimeMS' => 1, 'readConcern' => 1, 'readPreference' => 1, 'session' => 1]);
 
-        $this->count = $this->createCount();
+        if (isset($options['maxTimeMS']) && ! is_integer($options['maxTimeMS'])) {
+            throw InvalidArgumentException::invalidType('"maxTimeMS" option', $options['maxTimeMS'], 'integer');
+        }
+
+        if (isset($options['readConcern']) && ! $options['readConcern'] instanceof ReadConcern) {
+            throw InvalidArgumentException::invalidType('"readConcern" option', $options['readConcern'], ReadConcern::class);
+        }
+
+        if (isset($options['readPreference']) && ! $options['readPreference'] instanceof ReadPreference) {
+            throw InvalidArgumentException::invalidType('"readPreference" option', $options['readPreference'], ReadPreference::class);
+        }
+
+        if (isset($options['session']) && ! $options['session'] instanceof Session) {
+            throw InvalidArgumentException::invalidType('"session" option', $options['session'], Session::class);
+        }
+
+        $this->options = array_intersect_key($options, ['comment' => 1, 'maxTimeMS' => 1, 'readConcern' => 1, 'readPreference' => 1, 'session' => 1]);
     }
 
     /**
@@ -90,18 +113,22 @@ class EstimatedDocumentCount implements Executable, Explainable
      */
     public function execute(Server $server)
     {
-        return $this->count->execute($server);
-    }
-
-    public function getCommandDocument(Server $server)
-    {
-        return $this->count->getCommandDocument($server);
+        return $this->createCount()->execute($server);
     }
 
     /**
-     * @return Count
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
      */
-    private function createCount()
+    public function getCommandDocument(Server $server)
+    {
+        return $this->createCount()->getCommandDocument($server);
+    }
+
+    private function createCount(): Count
     {
         return new Count($this->databaseName, $this->collectionName, [], $this->options);
     }

cache/stores/mongodb/MongoDB/Operation/Executable.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,

cache/stores/mongodb/MongoDB/Operation/Explain.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2018 MongoDB, Inc.
+ * Copyright 2018-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -18,11 +18,13 @@
 namespace MongoDB\Operation;
 
 use MongoDB\Driver\Command;
+use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
 use MongoDB\Driver\ReadPreference;
 use MongoDB\Driver\Server;
 use MongoDB\Driver\Session;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
+
 use function current;
 use function is_array;
 use function is_string;
@@ -33,23 +35,17 @@ use function MongoDB\server_supports_feature;
  *
  * @api
  * @see \MongoDB\Collection::explain()
- * @see http://docs.mongodb.org/manual/reference/command/explain/
+ * @see https://mongodb.com/docs/manual/reference/command/explain/
  */
 class Explain implements Executable
 {
-    const VERBOSITY_ALL_PLANS = 'allPlansExecution';
-    const VERBOSITY_EXEC_STATS = 'executionStats';
-    const VERBOSITY_QUERY = 'queryPlanner';
+    public const VERBOSITY_ALL_PLANS = 'allPlansExecution';
+    public const VERBOSITY_EXEC_STATS = 'executionStats';
+    public const VERBOSITY_QUERY = 'queryPlanner';
 
     /** @var integer */
     private static $wireVersionForAggregate = 7;
 
-    /** @var integer */
-    private static $wireVersionForDistinct = 4;
-
-    /** @var integer */
-    private static $wireVersionForFindAndModify = 4;
-
     /** @var string */
     private $databaseName;
 
@@ -64,6 +60,10 @@ class Explain implements Executable
      *
      * Supported options:
      *
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
+     *
      *  * readPreference (MongoDB\Driver\ReadPreference): Read preference.
      *
      *  * session (MongoDB\Driver\Session): Client session.
@@ -101,27 +101,22 @@ class Explain implements Executable
         $this->options = $options;
     }
 
+    /**
+     * Execute the operation.
+     *
+     * @see Executable::execute()
+     * @param Server $server
+     * @return array|object
+     * @throws UnsupportedException if the server does not support explaining the operation
+     * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
+     */
     public function execute(Server $server)
     {
-        if ($this->explainable instanceof Distinct && ! server_supports_feature($server, self::$wireVersionForDistinct)) {
-            throw UnsupportedException::explainNotSupported();
-        }
-
-        if ($this->isFindAndModify($this->explainable) && ! server_supports_feature($server, self::$wireVersionForFindAndModify)) {
-            throw UnsupportedException::explainNotSupported();
-        }
-
         if ($this->explainable instanceof Aggregate && ! server_supports_feature($server, self::$wireVersionForAggregate)) {
             throw UnsupportedException::explainNotSupported();
         }
 
-        $cmd = ['explain' => $this->explainable->getCommandDocument($server)];
-
-        if (isset($this->options['verbosity'])) {
-            $cmd['verbosity'] = $this->options['verbosity'];
-        }
-
-        $cursor = $server->executeCommand($this->databaseName, new Command($cmd), $this->createOptions());
+        $cursor = $server->executeCommand($this->databaseName, $this->createCommand($server), $this->createOptions());
 
         if (isset($this->options['typeMap'])) {
             $cursor->setTypeMap($this->options['typeMap']);
@@ -130,10 +125,29 @@ class Explain implements Executable
         return current($cursor->toArray());
     }
 
+    /**
+     * Create the explain command.
+     *
+     * @param Server $server
+     * @return Command
+     */
+    private function createCommand(Server $server)
+    {
+        $cmd = ['explain' => $this->explainable->getCommandDocument($server)];
+
+        foreach (['comment', 'verbosity'] as $option) {
+            if (isset($this->options[$option])) {
+                $cmd[$option] = $this->options[$option];
+            }
+        }
+
+        return new Command($cmd);
+    }
+
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executecommand.php
      * @return array
      */
     private function createOptions()
@@ -151,7 +165,7 @@ class Explain implements Executable
         return $options;
     }
 
-    private function isFindAndModify($explainable)
+    private function isFindAndModify(Explainable $explainable): bool
     {
         if ($explainable instanceof FindAndModify || $explainable instanceof FindOneAndDelete || $explainable instanceof FindOneAndReplace || $explainable instanceof FindOneAndUpdate) {
             return true;

cache/stores/mongodb/MongoDB/Operation/Explainable.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2018 MongoDB, Inc.
+ * Copyright 2018-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -27,5 +27,11 @@ use MongoDB\Driver\Server;
  */
 interface Explainable extends Executable
 {
+    /**
+     * Returns the command document for this operation.
+     *
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server);
 }

cache/stores/mongodb/MongoDB/Operation/Find.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -26,13 +26,14 @@ use MongoDB\Driver\Server;
 use MongoDB\Driver\Session;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
+
 use function is_array;
 use function is_bool;
 use function is_integer;
 use function is_object;
 use function is_string;
-use function MongoDB\server_supports_feature;
 use function trigger_error;
+
 use const E_USER_DEPRECATED;
 
 /**
@@ -40,23 +41,14 @@ use const E_USER_DEPRECATED;
  *
  * @api
  * @see \MongoDB\Collection::find()
- * @see http://docs.mongodb.org/manual/tutorial/query-documents/
- * @see http://docs.mongodb.org/manual/reference/operator/query-modifier/
+ * @see https://mongodb.com/docs/manual/tutorial/query-documents/
+ * @see https://mongodb.com/docs/manual/reference/operator/query-modifier/
  */
 class Find implements Executable, Explainable
 {
-    const NON_TAILABLE = 1;
-    const TAILABLE = 2;
-    const TAILABLE_AWAIT = 3;
-
-    /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var integer */
-    private static $wireVersionForReadConcern = 4;
-
-    /** @var integer */
-    private static $wireVersionForAllowDiskUseServerSideError = 4;
+    public const NON_TAILABLE = 1;
+    public const TAILABLE = 2;
+    public const TAILABLE_AWAIT = 3;
 
     /** @var string */
     private $databaseName;
@@ -77,7 +69,7 @@ class Find implements Executable, Explainable
      *
      *  * allowDiskUse (boolean): Enables writing to temporary files. When set
      *    to true, queries can write data to the _tmp sub-directory in the
-     *    dbPath directory. The default is false.
+     *    dbPath directory.
      *
      *  * allowPartialResults (boolean): Get partial results from a mongos if
      *    some shards are inaccessible (instead of throwing an error).
@@ -86,11 +78,9 @@ class Find implements Executable, Explainable
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
      *
-     *  * comment (string): Attaches a comment to the query. If "$comment" also
-     *    exists in the modifiers document, this option will take precedence.
+     *    Only string values are supported for server versions < 4.4.
      *
      *  * cursorType (enum): Indicates the type of cursor to use. Must be either
      *    NON_TAILABLE, TAILABLE, or TAILABLE_AWAIT. The default is
@@ -134,9 +124,6 @@ class Find implements Executable, Explainable
      *
      *  * readConcern (MongoDB\Driver\ReadConcern): Read concern.
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
-     *
      *  * readPreference (MongoDB\Driver\ReadPreference): Read preference.
      *
      *  * returnKey (boolean): If true, returns only the index keys in the
@@ -144,8 +131,6 @@ class Find implements Executable, Explainable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * showRecordId (boolean): Determines whether to return the record
      *    identifier for each document. If true, adds a field $recordId to the
      *    returned documents.
@@ -161,6 +146,11 @@ class Find implements Executable, Explainable
      *    "$orderby" also exists in the modifiers document, this option will
      *    take precedence.
      *
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
+     *
      *  * typeMap (array): Type map for BSON deserialization. This will be
      *    applied to the returned Cursor (it is not sent to the server).
      *
@@ -192,18 +182,16 @@ class Find implements Executable, Explainable
             throw InvalidArgumentException::invalidType('"collation" option', $options['collation'], 'array or object');
         }
 
-        if (isset($options['comment']) && ! is_string($options['comment'])) {
-            throw InvalidArgumentException::invalidType('"comment" option', $options['comment'], 'comment');
-        }
-
         if (isset($options['cursorType'])) {
             if (! is_integer($options['cursorType'])) {
                 throw InvalidArgumentException::invalidType('"cursorType" option', $options['cursorType'], 'integer');
             }
 
-            if ($options['cursorType'] !== self::NON_TAILABLE &&
+            if (
+                $options['cursorType'] !== self::NON_TAILABLE &&
                 $options['cursorType'] !== self::TAILABLE &&
-                $options['cursorType'] !== self::TAILABLE_AWAIT) {
+                $options['cursorType'] !== self::TAILABLE_AWAIT
+            ) {
                 throw new InvalidArgumentException('Invalid value for "cursorType" option: ' . $options['cursorType']);
             }
         }
@@ -288,6 +276,10 @@ class Find implements Executable, Explainable
             throw InvalidArgumentException::invalidType('"typeMap" option', $options['typeMap'], 'array');
         }
 
+        if (isset($options['let']) && ! is_array($options['let']) && ! is_object($options['let'])) {
+            throw InvalidArgumentException::invalidType('"let" option', $options['let'], 'array or object');
+        }
+
         if (isset($options['readConcern']) && $options['readConcern']->isDefault()) {
             unset($options['readConcern']);
         }
@@ -312,23 +304,11 @@ class Find implements Executable, Explainable
      * @see Executable::execute()
      * @param Server $server
      * @return Cursor
-     * @throws UnsupportedException if collation or read concern is used and unsupported
+     * @throws UnsupportedException if read concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['collation']) && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
-        if (isset($this->options['readConcern']) && ! server_supports_feature($server, self::$wireVersionForReadConcern)) {
-            throw UnsupportedException::readConcernNotSupported();
-        }
-
-        if (isset($this->options['allowDiskUse']) && ! server_supports_feature($server, self::$wireVersionForAllowDiskUseServerSideError)) {
-            throw UnsupportedException::allowDiskUseNotSupported();
-        }
-
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
         if ($inTransaction && isset($this->options['readConcern'])) {
             throw UnsupportedException::readConcernNotSupportedInTransaction();
@@ -343,6 +323,13 @@ class Find implements Executable, Explainable
         return $cursor;
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->createCommandDocument();
@@ -351,7 +338,7 @@ class Find implements Executable, Explainable
     /**
      * Construct a command document for Find
      */
-    private function createCommandDocument()
+    private function createCommandDocument(): array
     {
         $cmd = ['find' => $this->collectionName, 'filter' => (object) $this->filter];
 
@@ -383,6 +370,7 @@ class Find implements Executable, Explainable
                 $options[$modifier[0]] = $options['modifiers'][$modifier[1]];
             }
         }
+
         unset($options['modifiers']);
 
         return $cmd + $options;
@@ -391,7 +379,7 @@ class Find implements Executable, Explainable
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executequery.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executequery.php
      * @return array
      */
     private function createExecuteOptions()
@@ -425,6 +413,7 @@ class Find implements Executable, Explainable
             if ($this->options['cursorType'] === self::TAILABLE) {
                 $options['tailable'] = true;
             }
+
             if ($this->options['cursorType'] === self::TAILABLE_AWAIT) {
                 $options['tailable'] = true;
                 $options['awaitData'] = true;
@@ -437,7 +426,7 @@ class Find implements Executable, Explainable
             }
         }
 
-        foreach (['collation', 'max', 'min'] as $option) {
+        foreach (['collation', 'let', 'max', 'min'] as $option) {
             if (isset($this->options[$option])) {
                 $options[$option] = (object) $this->options[$option];
             }

cache/stores/mongodb/MongoDB/Operation/FindAndModify.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -25,6 +25,8 @@ use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnexpectedValueException;
 use MongoDB\Exception\UnsupportedException;
+
+use function array_key_exists;
 use function current;
 use function is_array;
 use function is_bool;
@@ -33,6 +35,7 @@ use function is_object;
 use function is_string;
 use function MongoDB\create_field_path_type_map;
 use function MongoDB\is_pipeline;
+use function MongoDB\is_write_concern_acknowledged;
 use function MongoDB\server_supports_feature;
 
 /**
@@ -42,27 +45,15 @@ use function MongoDB\server_supports_feature;
  * FindOneAndUpdate operation classes.
  *
  * @internal
- * @see http://docs.mongodb.org/manual/reference/command/findAndModify/
+ * @see https://mongodb.com/docs/manual/reference/command/findAndModify/
  */
 class FindAndModify implements Executable, Explainable
 {
-    /** @var integer */
-    private static $wireVersionForArrayFilters = 6;
-
-    /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var integer */
-    private static $wireVersionForDocumentLevelValidation = 4;
-
     /** @var integer */
     private static $wireVersionForHint = 9;
 
     /** @var integer */
-    private static $wireVersionForHintServerSideError = 8;
-
-    /** @var integer */
-    private static $wireVersionForWriteConcern = 4;
+    private static $wireVersionForUnsupportedOptionServerSideError = 8;
 
     /** @var string */
     private $databaseName;
@@ -81,20 +72,15 @@ class FindAndModify implements Executable, Explainable
      *  * arrayFilters (document array): A set of filters specifying to which
      *    array elements an update should apply.
      *
-     *    This is not supported for server versions < 3.6 and will result in an
-     *    exception at execution time if used.
-     *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * bypassDocumentValidation (boolean): If true, allows the write to
      *    circumvent document level validation.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
-     *
      *  * fields (document): Limits the fields to return for the matching
      *    document.
      *
@@ -119,8 +105,6 @@ class FindAndModify implements Executable, Explainable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * sort (document): Determines which document the operation modifies if
      *    the query selects multiple documents.
      *
@@ -133,10 +117,12 @@ class FindAndModify implements Executable, Explainable
      *    matches the query. This option is ignored for remove operations. The
      *    default is false.
      *
-     *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
+     *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
      * @param string $databaseName   Database name
      * @param string $collectionName Collection name
@@ -145,11 +131,7 @@ class FindAndModify implements Executable, Explainable
      */
     public function __construct($databaseName, $collectionName, array $options)
     {
-        $options += [
-            'new' => false,
-            'remove' => false,
-            'upsert' => false,
-        ];
+        $options += ['remove' => false];
 
         if (isset($options['arrayFilters']) && ! is_array($options['arrayFilters'])) {
             throw InvalidArgumentException::invalidType('"arrayFilters" option', $options['arrayFilters'], 'array');
@@ -175,7 +157,7 @@ class FindAndModify implements Executable, Explainable
             throw InvalidArgumentException::invalidType('"maxTimeMS" option', $options['maxTimeMS'], 'integer');
         }
 
-        if (! is_bool($options['new'])) {
+        if (array_key_exists('new', $options) && ! is_bool($options['new'])) {
             throw InvalidArgumentException::invalidType('"new" option', $options['new'], 'boolean');
         }
 
@@ -207,10 +189,18 @@ class FindAndModify implements Executable, Explainable
             throw InvalidArgumentException::invalidType('"writeConcern" option', $options['writeConcern'], WriteConcern::class);
         }
 
-        if (! is_bool($options['upsert'])) {
+        if (array_key_exists('upsert', $options) && ! is_bool($options['upsert'])) {
             throw InvalidArgumentException::invalidType('"upsert" option', $options['upsert'], 'boolean');
         }
 
+        if (isset($options['let']) && ! is_array($options['let']) && ! is_object($options['let'])) {
+            throw InvalidArgumentException::invalidType('"let" option', $options['let'], 'array or object');
+        }
+
+        if (isset($options['bypassDocumentValidation']) && ! $options['bypassDocumentValidation']) {
+            unset($options['bypassDocumentValidation']);
+        }
+
         if (! (isset($options['update']) xor $options['remove'])) {
             throw new InvalidArgumentException('The "remove" option must be true or an "update" document must be specified, but not both');
         }
@@ -231,29 +221,24 @@ class FindAndModify implements Executable, Explainable
      * @param Server $server
      * @return array|object|null
      * @throws UnexpectedValueException if the command response was malformed
-     * @throws UnsupportedException if array filters, collation, or write concern is used and unsupported
+     * @throws UnsupportedException if hint or write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['arrayFilters']) && ! server_supports_feature($server, self::$wireVersionForArrayFilters)) {
-            throw UnsupportedException::arrayFiltersNotSupported();
-        }
-
-        if (isset($this->options['collation']) && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
-        /* Server versions >= 4.1.10 raise errors for unknown findAndModify
-         * options (SERVER-40005), but the CRUD spec requires client-side errors
-         * for server versions < 4.2. For later versions, we'll rely on the
-         * server to either utilize the option or report its own error. */
-        if (isset($this->options['hint']) && ! $this->isHintSupported($server)) {
+        /* Server versions >= 4.2.0 raise errors for unsupported update options.
+         * For previous versions, the CRUD spec requires a client-side error. */
+        if (isset($this->options['hint']) && ! server_supports_feature($server, self::$wireVersionForUnsupportedOptionServerSideError)) {
             throw UnsupportedException::hintNotSupported();
         }
 
-        if (isset($this->options['writeConcern']) && ! server_supports_feature($server, self::$wireVersionForWriteConcern)) {
-            throw UnsupportedException::writeConcernNotSupported();
+        /* CRUD spec requires a client-side error when using "hint" with an
+         * unacknowledged write concern on an unsupported server. */
+        if (
+            isset($this->options['writeConcern']) && ! is_write_concern_acknowledged($this->options['writeConcern']) &&
+            isset($this->options['hint']) && ! server_supports_feature($server, self::$wireVersionForHint)
+        ) {
+            throw UnsupportedException::hintNotSupported();
         }
 
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
@@ -261,7 +246,7 @@ class FindAndModify implements Executable, Explainable
             throw UnsupportedException::writeConcernNotSupportedInTransaction();
         }
 
-        $cursor = $server->executeWriteCommand($this->databaseName, new Command($this->createCommandDocument($server)), $this->createOptions());
+        $cursor = $server->executeWriteCommand($this->databaseName, new Command($this->createCommandDocument()), $this->createOptions());
 
         if (isset($this->options['typeMap'])) {
             $cursor->setTypeMap(create_field_path_type_map($this->options['typeMap'], 'value'));
@@ -272,29 +257,40 @@ class FindAndModify implements Executable, Explainable
         return $result->value ?? null;
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
-        return $this->createCommandDocument($server);
+        return $this->createCommandDocument();
     }
 
     /**
      * Create the findAndModify command document.
      *
-     * @param Server $server
      * @return array
      */
-    private function createCommandDocument(Server $server)
+    private function createCommandDocument()
     {
         $cmd = ['findAndModify' => $this->collectionName];
 
         if ($this->options['remove']) {
             $cmd['remove'] = true;
         } else {
-            $cmd['new'] = $this->options['new'];
-            $cmd['upsert'] = $this->options['upsert'];
+            if (isset($this->options['new'])) {
+                $cmd['new'] = $this->options['new'];
+            }
+
+            if (isset($this->options['upsert'])) {
+                $cmd['upsert'] = $this->options['upsert'];
+            }
         }
 
-        foreach (['collation', 'fields', 'query', 'sort'] as $option) {
+        foreach (['collation', 'fields', 'let', 'query', 'sort'] as $option) {
             if (isset($this->options[$option])) {
                 $cmd[$option] = (object) $this->options[$option];
             }
@@ -306,25 +302,19 @@ class FindAndModify implements Executable, Explainable
                 : (object) $this->options['update'];
         }
 
-        foreach (['arrayFilters', 'hint', 'maxTimeMS'] as $option) {
+        foreach (['arrayFilters', 'bypassDocumentValidation', 'comment', 'hint', 'maxTimeMS'] as $option) {
             if (isset($this->options[$option])) {
                 $cmd[$option] = $this->options[$option];
             }
         }
 
-        if (! empty($this->options['bypassDocumentValidation']) &&
-            server_supports_feature($server, self::$wireVersionForDocumentLevelValidation)
-        ) {
-            $cmd['bypassDocumentValidation'] = $this->options['bypassDocumentValidation'];
-        }
-
         return $cmd;
     }
 
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executewritecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executewritecommand.php
      * @return array
      */
     private function createOptions()
@@ -341,20 +331,4 @@ class FindAndModify implements Executable, Explainable
 
         return $options;
     }
-
-    private function isAcknowledgedWriteConcern() : bool
-    {
-        if (! isset($this->options['writeConcern'])) {
-            return true;
-        }
-
-        return $this->options['writeConcern']->getW() > 1 || $this->options['writeConcern']->getJournal();
-    }
-
-    private function isHintSupported(Server $server) : bool
-    {
-        $requiredWireVersion = $this->isAcknowledgedWriteConcern() ? self::$wireVersionForHintServerSideError : self::$wireVersionForHint;
-
-        return server_supports_feature($server, $requiredWireVersion);
-    }
 }

cache/stores/mongodb/MongoDB/Operation/FindOne.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -21,6 +21,7 @@ use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
 use MongoDB\Driver\Server;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
+
 use function current;
 
 /**
@@ -28,8 +29,8 @@ use function current;
  *
  * @api
  * @see \MongoDB\Collection::findOne()
- * @see http://docs.mongodb.org/manual/tutorial/query-documents/
- * @see http://docs.mongodb.org/manual/reference/operator/query-modifier/
+ * @see https://mongodb.com/docs/manual/tutorial/query-documents/
+ * @see https://mongodb.com/docs/manual/reference/operator/query-modifier/
  */
 class FindOne implements Executable, Explainable
 {
@@ -43,11 +44,9 @@ class FindOne implements Executable, Explainable
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
      *
-     *  * comment (string): Attaches a comment to the query. If "$comment" also
-     *    exists in the modifiers document, this option will take precedence.
+     *    Only string values are supported for server versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -74,9 +73,6 @@ class FindOne implements Executable, Explainable
      *
      *  * readConcern (MongoDB\Driver\ReadConcern): Read concern.
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
-     *
      *  * readPreference (MongoDB\Driver\ReadPreference): Read preference.
      *
      *  * returnKey (boolean): If true, returns only the index keys in the
@@ -84,8 +80,6 @@ class FindOne implements Executable, Explainable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * showRecordId (boolean): Determines whether to return the record
      *    identifier for each document. If true, adds a field $recordId to the
      *    returned documents.
@@ -96,6 +90,11 @@ class FindOne implements Executable, Explainable
      *    "$orderby" also exists in the modifiers document, this option will
      *    take precedence.
      *
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
+     *
      *  * typeMap (array): Type map for BSON deserialization.
      *
      * @param string       $databaseName   Database name
@@ -131,6 +130,13 @@ class FindOne implements Executable, Explainable
         return $document === false ? null : $document;
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->find->getCommandDocument($server);

cache/stores/mongodb/MongoDB/Operation/FindOneAndDelete.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -21,6 +21,7 @@ use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
 use MongoDB\Driver\Server;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
+
 use function is_array;
 use function is_object;
 
@@ -29,7 +30,7 @@ use function is_object;
  *
  * @api
  * @see \MongoDB\Collection::findOneAndDelete()
- * @see http://docs.mongodb.org/manual/reference/command/findAndModify/
+ * @see https://mongodb.com/docs/manual/reference/command/findAndModify/
  */
 class FindOneAndDelete implements Executable, Explainable
 {
@@ -43,8 +44,9 @@ class FindOneAndDelete implements Executable, Explainable
      *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -61,18 +63,18 @@ class FindOneAndDelete implements Executable, Explainable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * sort (document): Determines which document the operation modifies if
      *    the query selects multiple documents.
      *
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
+     *
      *  * typeMap (array): Type map for BSON deserialization.
      *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
-     *
      * @param string       $databaseName   Database name
      * @param string       $collectionName Collection name
      * @param array|object $filter         Query by which to filter documents
@@ -116,6 +118,13 @@ class FindOneAndDelete implements Executable, Explainable
         return $this->findAndModify->execute($server);
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->findAndModify->getCommandDocument($server);

cache/stores/mongodb/MongoDB/Operation/FindOneAndReplace.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -21,6 +21,8 @@ use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
 use MongoDB\Driver\Server;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
+
+use function array_key_exists;
 use function is_array;
 use function is_integer;
 use function is_object;
@@ -31,12 +33,12 @@ use function MongoDB\is_first_key_operator;
  *
  * @api
  * @see \MongoDB\Collection::findOneAndReplace()
- * @see http://docs.mongodb.org/manual/reference/command/findAndModify/
+ * @see https://mongodb.com/docs/manual/reference/command/findAndModify/
  */
 class FindOneAndReplace implements Executable, Explainable
 {
-    const RETURN_DOCUMENT_BEFORE = 1;
-    const RETURN_DOCUMENT_AFTER = 2;
+    public const RETURN_DOCUMENT_BEFORE = 1;
+    public const RETURN_DOCUMENT_AFTER = 2;
 
     /** @var FindAndModify */
     private $findAndModify;
@@ -49,13 +51,11 @@ class FindOneAndReplace implements Executable, Explainable
      *  * bypassDocumentValidation (boolean): If true, allows the write to
      *    circumvent document level validation.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
-     *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -78,8 +78,6 @@ class FindOneAndReplace implements Executable, Explainable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * sort (document): Determines which document the operation modifies if
      *    the query selects multiple documents.
      *
@@ -88,10 +86,12 @@ class FindOneAndReplace implements Executable, Explainable
      *  * upsert (boolean): When true, a new document is created if no document
      *    matches the query. The default is false.
      *
-     *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
+     *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
      * @param string       $databaseName   Database name
      * @param string       $collectionName Collection name
@@ -114,21 +114,19 @@ class FindOneAndReplace implements Executable, Explainable
             throw new InvalidArgumentException('First key in $replacement argument is an update operator');
         }
 
-        $options += [
-            'returnDocument' => self::RETURN_DOCUMENT_BEFORE,
-            'upsert' => false,
-        ];
-
         if (isset($options['projection']) && ! is_array($options['projection']) && ! is_object($options['projection'])) {
             throw InvalidArgumentException::invalidType('"projection" option', $options['projection'], 'array or object');
         }
 
-        if (! is_integer($options['returnDocument'])) {
+        if (array_key_exists('returnDocument', $options) && ! is_integer($options['returnDocument'])) {
             throw InvalidArgumentException::invalidType('"returnDocument" option', $options['returnDocument'], 'integer');
         }
 
-        if ($options['returnDocument'] !== self::RETURN_DOCUMENT_AFTER &&
-            $options['returnDocument'] !== self::RETURN_DOCUMENT_BEFORE) {
+        if (
+            isset($options['returnDocument']) &&
+            $options['returnDocument'] !== self::RETURN_DOCUMENT_AFTER &&
+            $options['returnDocument'] !== self::RETURN_DOCUMENT_BEFORE
+        ) {
             throw new InvalidArgumentException('Invalid value for "returnDocument" option: ' . $options['returnDocument']);
         }
 
@@ -136,7 +134,9 @@ class FindOneAndReplace implements Executable, Explainable
             $options['fields'] = $options['projection'];
         }
 
-        $options['new'] = $options['returnDocument'] === self::RETURN_DOCUMENT_AFTER;
+        if (isset($options['returnDocument'])) {
+            $options['new'] = $options['returnDocument'] === self::RETURN_DOCUMENT_AFTER;
+        }
 
         unset($options['projection'], $options['returnDocument']);
 
@@ -161,6 +161,13 @@ class FindOneAndReplace implements Executable, Explainable
         return $this->findAndModify->execute($server);
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->findAndModify->getCommandDocument($server);

cache/stores/mongodb/MongoDB/Operation/FindOneAndUpdate.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -21,6 +21,8 @@ use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
 use MongoDB\Driver\Server;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
+
+use function array_key_exists;
 use function is_array;
 use function is_integer;
 use function is_object;
@@ -32,12 +34,12 @@ use function MongoDB\is_pipeline;
  *
  * @api
  * @see \MongoDB\Collection::findOneAndUpdate()
- * @see http://docs.mongodb.org/manual/reference/command/findAndModify/
+ * @see https://mongodb.com/docs/manual/reference/command/findAndModify/
  */
 class FindOneAndUpdate implements Executable, Explainable
 {
-    const RETURN_DOCUMENT_BEFORE = 1;
-    const RETURN_DOCUMENT_AFTER = 2;
+    public const RETURN_DOCUMENT_BEFORE = 1;
+    public const RETURN_DOCUMENT_AFTER = 2;
 
     /** @var FindAndModify */
     private $findAndModify;
@@ -53,13 +55,11 @@ class FindOneAndUpdate implements Executable, Explainable
      *  * bypassDocumentValidation (boolean): If true, allows the write to
      *    circumvent document level validation.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
-     *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -82,8 +82,6 @@ class FindOneAndUpdate implements Executable, Explainable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * sort (document): Determines which document the operation modifies if
      *    the query selects multiple documents.
      *
@@ -92,10 +90,12 @@ class FindOneAndUpdate implements Executable, Explainable
      *  * upsert (boolean): When true, a new document is created if no document
      *    matches the query. The default is false.
      *
-     *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
+     *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
      * @param string       $databaseName   Database name
      * @param string       $collectionName Collection name
@@ -118,21 +118,19 @@ class FindOneAndUpdate implements Executable, Explainable
             throw new InvalidArgumentException('Expected an update document with operator as first key or a pipeline');
         }
 
-        $options += [
-            'returnDocument' => self::RETURN_DOCUMENT_BEFORE,
-            'upsert' => false,
-        ];
-
         if (isset($options['projection']) && ! is_array($options['projection']) && ! is_object($options['projection'])) {
             throw InvalidArgumentException::invalidType('"projection" option', $options['projection'], 'array or object');
         }
 
-        if (! is_integer($options['returnDocument'])) {
+        if (array_key_exists('returnDocument', $options) && ! is_integer($options['returnDocument'])) {
             throw InvalidArgumentException::invalidType('"returnDocument" option', $options['returnDocument'], 'integer');
         }
 
-        if ($options['returnDocument'] !== self::RETURN_DOCUMENT_AFTER &&
-            $options['returnDocument'] !== self::RETURN_DOCUMENT_BEFORE) {
+        if (
+            isset($options['returnDocument']) &&
+            $options['returnDocument'] !== self::RETURN_DOCUMENT_AFTER &&
+            $options['returnDocument'] !== self::RETURN_DOCUMENT_BEFORE
+        ) {
             throw new InvalidArgumentException('Invalid value for "returnDocument" option: ' . $options['returnDocument']);
         }
 
@@ -140,7 +138,9 @@ class FindOneAndUpdate implements Executable, Explainable
             $options['fields'] = $options['projection'];
         }
 
-        $options['new'] = $options['returnDocument'] === self::RETURN_DOCUMENT_AFTER;
+        if (isset($options['returnDocument'])) {
+            $options['new'] = $options['returnDocument'] === self::RETURN_DOCUMENT_AFTER;
+        }
 
         unset($options['projection'], $options['returnDocument']);
 
@@ -165,6 +165,13 @@ class FindOneAndUpdate implements Executable, Explainable
         return $this->findAndModify->execute($server);
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->findAndModify->getCommandDocument($server);

cache/stores/mongodb/MongoDB/Operation/InsertMany.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -25,10 +25,10 @@ use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
 use MongoDB\InsertManyResult;
+
 use function is_array;
 use function is_bool;
 use function is_object;
-use function MongoDB\server_supports_feature;
 use function sprintf;
 
 /**
@@ -36,13 +36,10 @@ use function sprintf;
  *
  * @api
  * @see \MongoDB\Collection::insertMany()
- * @see http://docs.mongodb.org/manual/reference/command/insert/
+ * @see https://mongodb.com/docs/manual/reference/command/insert/
  */
 class InsertMany implements Executable
 {
-    /** @var integer */
-    private static $wireVersionForDocumentLevelValidation = 4;
-
     /** @var string */
     private $databaseName;
 
@@ -63,8 +60,10 @@ class InsertMany implements Executable
      *  * bypassDocumentValidation (boolean): If true, allows the write to
      *    circumvent document level validation.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
+     *  * comment (mixed): BSON value to attach as a comment to the command(s)
+     *    associated with this insert.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * ordered (boolean): If true, when an insert fails, return without
      *    performing the remaining writes. If false, when a write fails,
@@ -72,8 +71,6 @@ class InsertMany implements Executable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
      * @param string           $databaseName   Database name
@@ -120,6 +117,10 @@ class InsertMany implements Executable
             throw InvalidArgumentException::invalidType('"writeConcern" option', $options['writeConcern'], WriteConcern::class);
         }
 
+        if (isset($options['bypassDocumentValidation']) && ! $options['bypassDocumentValidation']) {
+            unset($options['bypassDocumentValidation']);
+        }
+
         if (isset($options['writeConcern']) && $options['writeConcern']->isDefault()) {
             unset($options['writeConcern']);
         }
@@ -136,6 +137,7 @@ class InsertMany implements Executable
      * @see Executable::execute()
      * @param Server $server
      * @return InsertManyResult
+     * @throws UnsupportedException if write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
@@ -145,33 +147,44 @@ class InsertMany implements Executable
             throw UnsupportedException::writeConcernNotSupportedInTransaction();
         }
 
-        $options = ['ordered' => $this->options['ordered']];
-
-        if (! empty($this->options['bypassDocumentValidation']) &&
-            server_supports_feature($server, self::$wireVersionForDocumentLevelValidation)
-        ) {
-            $options['bypassDocumentValidation'] = $this->options['bypassDocumentValidation'];
-        }
-
-        $bulk = new Bulk($options);
+        $bulk = new Bulk($this->createBulkWriteOptions());
         $insertedIds = [];
 
         foreach ($this->documents as $i => $document) {
             $insertedIds[$i] = $bulk->insert($document);
         }
 
-        $writeResult = $server->executeBulkWrite($this->databaseName . '.' . $this->collectionName, $bulk, $this->createOptions());
+        $writeResult = $server->executeBulkWrite($this->databaseName . '.' . $this->collectionName, $bulk, $this->createExecuteOptions());
 
         return new InsertManyResult($writeResult, $insertedIds);
     }
 
     /**
-     * Create options for executing the bulk write.
+     * Create options for constructing the bulk write.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executebulkwrite.php
+     * @see https://php.net/manual/en/mongodb-driver-bulkwrite.construct.php
      * @return array
      */
-    private function createOptions()
+    private function createBulkWriteOptions()
+    {
+        $options = ['ordered' => $this->options['ordered']];
+
+        foreach (['bypassDocumentValidation', 'comment'] as $option) {
+            if (isset($this->options[$option])) {
+                $options[$option] = $this->options[$option];
+            }
+        }
+
+        return $options;
+    }
+
+    /**
+     * Create options for executing the bulk write.
+     *
+     * @see https://php.net/manual/en/mongodb-driver-server.executebulkwrite.php
+     * @return array
+     */
+    private function createExecuteOptions()
     {
         $options = [];
 

cache/stores/mongodb/MongoDB/Operation/InsertOne.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -25,23 +25,20 @@ use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
 use MongoDB\InsertOneResult;
+
 use function is_array;
 use function is_bool;
 use function is_object;
-use function MongoDB\server_supports_feature;
 
 /**
  * Operation for inserting a single document with the insert command.
  *
  * @api
  * @see \MongoDB\Collection::insertOne()
- * @see http://docs.mongodb.org/manual/reference/command/insert/
+ * @see https://mongodb.com/docs/manual/reference/command/insert/
  */
 class InsertOne implements Executable
 {
-    /** @var integer */
-    private static $wireVersionForDocumentLevelValidation = 4;
-
     /** @var string */
     private $databaseName;
 
@@ -62,13 +59,12 @@ class InsertOne implements Executable
      *  * bypassDocumentValidation (boolean): If true, allows the write to
      *    circumvent document level validation.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
      * @param string       $databaseName   Database name
@@ -95,6 +91,10 @@ class InsertOne implements Executable
             throw InvalidArgumentException::invalidType('"writeConcern" option', $options['writeConcern'], WriteConcern::class);
         }
 
+        if (isset($options['bypassDocumentValidation']) && ! $options['bypassDocumentValidation']) {
+            unset($options['bypassDocumentValidation']);
+        }
+
         if (isset($options['writeConcern']) && $options['writeConcern']->isDefault()) {
             unset($options['writeConcern']);
         }
@@ -111,38 +111,50 @@ class InsertOne implements Executable
      * @see Executable::execute()
      * @param Server $server
      * @return InsertOneResult
+     * @throws UnsupportedException if write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        $options = [];
-
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
         if (isset($this->options['writeConcern']) && $inTransaction) {
             throw UnsupportedException::writeConcernNotSupportedInTransaction();
         }
 
-        if (! empty($this->options['bypassDocumentValidation']) &&
-            server_supports_feature($server, self::$wireVersionForDocumentLevelValidation)
-        ) {
-            $options['bypassDocumentValidation'] = $this->options['bypassDocumentValidation'];
-        }
-
-        $bulk = new Bulk($options);
+        $bulk = new Bulk($this->createBulkWriteOptions());
         $insertedId = $bulk->insert($this->document);
 
-        $writeResult = $server->executeBulkWrite($this->databaseName . '.' . $this->collectionName, $bulk, $this->createOptions());
+        $writeResult = $server->executeBulkWrite($this->databaseName . '.' . $this->collectionName, $bulk, $this->createExecuteOptions());
 
         return new InsertOneResult($writeResult, $insertedId);
     }
 
     /**
-     * Create options for executing the bulk write.
+     * Create options for constructing the bulk write.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executebulkwrite.php
+     * @see https://php.net/manual/en/mongodb-driver-bulkwrite.construct.php
      * @return array
      */
-    private function createOptions()
+    private function createBulkWriteOptions()
+    {
+        $options = [];
+
+        foreach (['bypassDocumentValidation', 'comment'] as $option) {
+            if (isset($this->options[$option])) {
+                $options[$option] = $this->options[$option];
+            }
+        }
+
+        return $options;
+    }
+
+    /**
+     * Create options for executing the bulk write.
+     *
+     * @see https://php.net/manual/en/mongodb-driver-server.executebulkwrite.php
+     * @return array
+     */
+    private function createExecuteOptions()
     {
         $options = [];
 

cache/stores/mongodb/MongoDB/Operation/ListCollectionNames.php

@@ -6,7 +6,7 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -29,7 +29,7 @@ use MongoDB\Model\CallbackIterator;
  *
  * @api
  * @see \MongoDB\Database::listCollectionNames()
- * @see http://docs.mongodb.org/manual/reference/command/listCollections/
+ * @see https://mongodb.com/docs/manual/reference/command/listCollections/
  */
 class ListCollectionNames implements Executable
 {
@@ -41,6 +41,15 @@ class ListCollectionNames implements Executable
      *
      * Supported options:
      *
+     *  * authorizedCollections (boolean): Determines which collections are
+     *    returned based on the user privileges.
+     *
+     *    For servers < 4.0, this option is ignored.
+     *
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
+     *
      *  * filter (document): Query by which to filter collections.
      *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
@@ -48,8 +57,6 @@ class ListCollectionNames implements Executable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      * @param string $databaseName Database name
      * @param array  $options      Command options
      * @throws InvalidArgumentException for parameter/option parsing errors
@@ -67,7 +74,7 @@ class ListCollectionNames implements Executable
      * @return Iterator
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
-    public function execute(Server $server) : Iterator
+    public function execute(Server $server): Iterator
     {
         return new CallbackIterator(
             $this->listCollections->execute($server),

cache/stores/mongodb/MongoDB/Operation/ListCollections.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -29,7 +29,7 @@ use MongoDB\Model\CollectionInfoIterator;
  *
  * @api
  * @see \MongoDB\Database::listCollections()
- * @see http://docs.mongodb.org/manual/reference/command/listCollections/
+ * @see https://mongodb.com/docs/manual/reference/command/listCollections/
  */
 class ListCollections implements Executable
 {
@@ -44,6 +44,15 @@ class ListCollections implements Executable
      *
      * Supported options:
      *
+     *  * authorizedCollections (boolean): Determines which collections are
+     *    returned based on the user privileges.
+     *
+     *    For servers < 4.0, this option is ignored.
+     *
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
+     *
      *  * filter (document): Query by which to filter collections.
      *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
@@ -51,8 +60,6 @@ class ListCollections implements Executable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      * @param string $databaseName Database name
      * @param array  $options      Command options
      * @throws InvalidArgumentException for parameter/option parsing errors

cache/stores/mongodb/MongoDB/Operation/ListDatabaseNames.php

@@ -6,7 +6,7 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -24,6 +24,7 @@ use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
 use MongoDB\Driver\Server;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnexpectedValueException;
+
 use function array_column;
 
 /**
@@ -31,7 +32,7 @@ use function array_column;
  *
  * @api
  * @see \MongoDB\Client::listDatabaseNames()
- * @see http://docs.mongodb.org/manual/reference/command/ListDatabases/
+ * @see https://mongodb.com/docs/manual/reference/command/listDatabases/#mongodb-dbcommand-dbcmd.listDatabases
  */
 class ListDatabaseNames implements Executable
 {
@@ -48,17 +49,17 @@ class ListDatabaseNames implements Executable
      *
      *    For servers < 4.0.5, this option is ignored.
      *
-     *  * filter (document): Query by which to filter databases.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
      *
-     *    For servers < 3.6, this option is ignored.
+     *    This is not supported for servers versions < 4.4.
+     *
+     *  * filter (document): Query by which to filter databases.
      *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
      *    run.
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      * @param array $options Command options
      * @throws InvalidArgumentException for parameter/option parsing errors
      */
@@ -76,7 +77,7 @@ class ListDatabaseNames implements Executable
      * @throws UnexpectedValueException if the command response was malformed
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
-    public function execute(Server $server) : Iterator
+    public function execute(Server $server): Iterator
     {
         $result = $this->listDatabases->execute($server);
 

cache/stores/mongodb/MongoDB/Operation/ListDatabases.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -30,7 +30,7 @@ use MongoDB\Model\DatabaseInfoLegacyIterator;
  *
  * @api
  * @see \MongoDB\Client::listDatabases()
- * @see http://docs.mongodb.org/manual/reference/command/ListDatabases/
+ * @see https://mongodb.com/docs/manual/reference/command/listDatabases/#mongodb-dbcommand-dbcmd.listDatabases`
  */
 class ListDatabases implements Executable
 {
@@ -47,17 +47,17 @@ class ListDatabases implements Executable
      *
      *    For servers < 4.0.5, this option is ignored.
      *
-     *  * filter (document): Query by which to filter databases.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
      *
-     *    For servers < 3.6, this option is ignored.
+     *    This is not supported for servers versions < 4.4.
+     *
+     *  * filter (document): Query by which to filter databases.
      *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
      *    run.
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      * @param array $options Command options
      * @throws InvalidArgumentException for parameter/option parsing errors
      */

cache/stores/mongodb/MongoDB/Operation/ListIndexes.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -19,6 +19,7 @@ namespace MongoDB\Operation;
 
 use EmptyIterator;
 use MongoDB\Driver\Command;
+use MongoDB\Driver\Exception\CommandException;
 use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
 use MongoDB\Driver\Server;
 use MongoDB\Driver\Session;
@@ -26,6 +27,7 @@ use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Model\CachingIterator;
 use MongoDB\Model\IndexInfoIterator;
 use MongoDB\Model\IndexInfoIteratorIterator;
+
 use function is_integer;
 
 /**
@@ -33,7 +35,7 @@ use function is_integer;
  *
  * @api
  * @see \MongoDB\Collection::listIndexes()
- * @see http://docs.mongodb.org/manual/reference/command/listIndexes/
+ * @see https://mongodb.com/docs/manual/reference/command/listIndexes/
  */
 class ListIndexes implements Executable
 {
@@ -57,13 +59,15 @@ class ListIndexes implements Executable
      *
      * Supported options:
      *
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
+     *
      *  * maxTimeMS (integer): The maximum amount of time to allow the query to
      *    run.
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      * @param string $databaseName   Database name
      * @param string $collectionName Collection name
      * @param array  $options        Command options
@@ -103,7 +107,7 @@ class ListIndexes implements Executable
      * Note: read preference is intentionally omitted, as the spec requires that
      * the command be executed on the primary.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executecommand.php
      * @return array
      */
     private function createOptions()
@@ -129,13 +133,15 @@ class ListIndexes implements Executable
     {
         $cmd = ['listIndexes' => $this->collectionName];
 
-        if (isset($this->options['maxTimeMS'])) {
-            $cmd['maxTimeMS'] = $this->options['maxTimeMS'];
+        foreach (['comment', 'maxTimeMS'] as $option) {
+            if (isset($this->options[$option])) {
+                $cmd[$option] = $this->options[$option];
+            }
         }
 
         try {
             $cursor = $server->executeReadCommand($this->databaseName, new Command($cmd), $this->createOptions());
-        } catch (DriverRuntimeException $e) {
+        } catch (CommandException $e) {
             /* The server may return an error if the collection does not exist.
              * Check for possible error codes (see: SERVER-20463) and return an
              * empty iterator instead of throwing.

cache/stores/mongodb/MongoDB/Operation/MapReduce.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -31,6 +31,7 @@ use MongoDB\Exception\UnexpectedValueException;
 use MongoDB\Exception\UnsupportedException;
 use MongoDB\MapReduceResult;
 use stdClass;
+
 use function current;
 use function is_array;
 use function is_bool;
@@ -39,8 +40,8 @@ use function is_object;
 use function is_string;
 use function MongoDB\create_field_path_type_map;
 use function MongoDB\is_mapreduce_output_inline;
-use function MongoDB\server_supports_feature;
 use function trigger_error;
+
 use const E_USER_DEPRECATED;
 
 /**
@@ -48,22 +49,10 @@ use const E_USER_DEPRECATED;
  *
  * @api
  * @see \MongoDB\Collection::mapReduce()
- * @see https://docs.mongodb.com/manual/reference/command/mapReduce/
+ * @see https://mongodb.com/docs/manual/reference/command/mapReduce/
  */
 class MapReduce implements Executable
 {
-    /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var integer */
-    private static $wireVersionForDocumentLevelValidation = 4;
-
-    /** @var integer */
-    private static $wireVersionForReadConcern = 4;
-
-    /** @var integer */
-    private static $wireVersionForWriteConcern = 4;
-
     /** @var string */
     private $databaseName;
 
@@ -111,13 +100,11 @@ class MapReduce implements Executable
      *    circumvent document level validation. This only applies when results
      *    are output to a collection.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
-     *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * finalize (MongoDB\BSON\JavascriptInterface): Follows the reduce method
      *    and modifies the output.
@@ -140,9 +127,6 @@ class MapReduce implements Executable
      *  * readConcern (MongoDB\Driver\ReadConcern): Read concern. This is not
      *    supported when results are returned inline.
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
-     *
      *  * readPreference (MongoDB\Driver\ReadPreference): Read preference.
      *
      *    This option is ignored if results are output to a collection.
@@ -152,8 +136,6 @@ class MapReduce implements Executable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * sort (document): Sorts the input documents. This option is useful for
      *    optimization. For example, specify the sort key to be the same as the
      *    emit key so that there are fewer reduce operations. The sort key must
@@ -168,9 +150,6 @@ class MapReduce implements Executable
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern. This only
      *    applies when results are output to a collection.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
-     *
      * @param string              $databaseName   Database name
      * @param string              $collectionName Collection name
      * @param JavascriptInterface $map            Map function
@@ -245,6 +224,10 @@ class MapReduce implements Executable
             throw InvalidArgumentException::invalidType('"writeConcern" option', $options['writeConcern'], WriteConcern::class);
         }
 
+        if (isset($options['bypassDocumentValidation']) && ! $options['bypassDocumentValidation']) {
+            unset($options['bypassDocumentValidation']);
+        }
+
         if (isset($options['readConcern']) && $options['readConcern']->isDefault()) {
             unset($options['readConcern']);
         }
@@ -283,28 +266,17 @@ class MapReduce implements Executable
      * @param Server $server
      * @return MapReduceResult
      * @throws UnexpectedValueException if the command response was malformed
-     * @throws UnsupportedException if collation, read concern, or write concern is used and unsupported
+     * @throws UnsupportedException if read concern or write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['collation']) && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
-        if (isset($this->options['readConcern']) && ! server_supports_feature($server, self::$wireVersionForReadConcern)) {
-            throw UnsupportedException::readConcernNotSupported();
-        }
-
-        if (isset($this->options['writeConcern']) && ! server_supports_feature($server, self::$wireVersionForWriteConcern)) {
-            throw UnsupportedException::writeConcernNotSupported();
-        }
-
         $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
         if ($inTransaction) {
             if (isset($this->options['readConcern'])) {
                 throw UnsupportedException::readConcernNotSupportedInTransaction();
             }
+
             if (isset($this->options['writeConcern'])) {
                 throw UnsupportedException::writeConcernNotSupportedInTransaction();
             }
@@ -312,7 +284,7 @@ class MapReduce implements Executable
 
         $hasOutputCollection = ! is_mapreduce_output_inline($this->out);
 
-        $command = $this->createCommand($server);
+        $command = $this->createCommand();
         $options = $this->createOptions($hasOutputCollection);
 
         /* If the mapReduce operation results in a write, use
@@ -360,10 +332,9 @@ class MapReduce implements Executable
     /**
      * Create the mapReduce command.
      *
-     * @param Server $server
      * @return Command
      */
-    private function createCommand(Server $server)
+    private function createCommand()
     {
         $cmd = [
             'mapReduce' => $this->collectionName,
@@ -372,7 +343,7 @@ class MapReduce implements Executable
             'out' => $this->out,
         ];
 
-        foreach (['finalize', 'jsMode', 'limit', 'maxTimeMS', 'verbose'] as $option) {
+        foreach (['bypassDocumentValidation', 'comment', 'finalize', 'jsMode', 'limit', 'maxTimeMS', 'verbose'] as $option) {
             if (isset($this->options[$option])) {
                 $cmd[$option] = $this->options[$option];
             }
@@ -384,12 +355,6 @@ class MapReduce implements Executable
             }
         }
 
-        if (! empty($this->options['bypassDocumentValidation']) &&
-            server_supports_feature($server, self::$wireVersionForDocumentLevelValidation)
-        ) {
-            $cmd['bypassDocumentValidation'] = $this->options['bypassDocumentValidation'];
-        }
-
         return new Command($cmd);
     }
 
@@ -430,8 +395,8 @@ class MapReduce implements Executable
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executereadcommand.php
-     * @see http://php.net/manual/en/mongodb-driver-server.executereadwritecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executereadcommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executereadwritecommand.php
      * @param boolean $hasOutputCollection
      * @return array
      */

cache/stores/mongodb/MongoDB/Operation/ModifyCollection.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2018 MongoDB, Inc.
+ * Copyright 2018-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -23,17 +23,16 @@ use MongoDB\Driver\Server;
 use MongoDB\Driver\Session;
 use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
-use MongoDB\Exception\UnsupportedException;
+
 use function current;
 use function is_array;
-use function MongoDB\server_supports_feature;
 
 /**
  * Operation for the collMod command.
  *
  * @api
  * @see \MongoDB\Database::modifyCollection()
- * @see http://docs.mongodb.org/manual/reference/command/collMod/
+ * @see https://mongodb.com/docs/manual/reference/command/collMod/
  */
 class ModifyCollection implements Executable
 {
@@ -54,18 +53,17 @@ class ModifyCollection implements Executable
      *
      * Supported options:
      *
-     *  * session (MongoDB\Driver\Session): Client session.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
      *
-     *    Sessions are not supported for server versions < 3.6.
+     *    This is not supported for servers versions < 4.4.
+     *
+     *  * session (MongoDB\Driver\Session): Client session.
      *
      *  * typeMap (array): Type map for BSON deserialization. This will only be
      *    used for the returned command result document.
      *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
-     *    This is not supported for server versions < 3.2 and will result in an
-     *    exception at execution time if used.
-     *
      * @param string $databaseName      Database name
      * @param string $collectionName    Collection or view to modify
      * @param array  $collectionOptions Collection or view options to assign
@@ -110,11 +108,7 @@ class ModifyCollection implements Executable
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['writeConcern']) && ! server_supports_feature($server, self::$wireVersionForWriteConcern)) {
-            throw UnsupportedException::writeConcernNotSupported();
-        }
-
-        $cursor = $server->executeWriteCommand($this->databaseName, new Command(['collMod' => $this->collectionName] + $this->collectionOptions), $this->createOptions());
+        $cursor = $server->executeWriteCommand($this->databaseName, $this->createCommand(), $this->createOptions());
 
         if (isset($this->options['typeMap'])) {
             $cursor->setTypeMap($this->options['typeMap']);
@@ -123,10 +117,21 @@ class ModifyCollection implements Executable
         return current($cursor->toArray());
     }
 
+    private function createCommand(): Command
+    {
+        $cmd = ['collMod' => $this->collectionName] + $this->collectionOptions;
+
+        if (isset($this->options['comment'])) {
+            $cmd['comment'] = $this->options['comment'];
+        }
+
+        return new Command($cmd);
+    }
+
     /**
      * Create options for executing the command.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executewritecommand.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executewritecommand.php
      * @return array
      */
     private function createOptions()

cache/stores/mongodb/MongoDB/Operation/RenameCollection.php

@@ -0,0 +1,169 @@
+<?php
+/*
+ * Copyright 2021-present MongoDB, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+namespace MongoDB\Operation;
+
+use MongoDB\Driver\Command;
+use MongoDB\Driver\Server;
+use MongoDB\Driver\Session;
+use MongoDB\Driver\WriteConcern;
+use MongoDB\Exception\InvalidArgumentException;
+use MongoDB\Exception\UnsupportedException;
+
+use function current;
+use function is_array;
+use function is_bool;
+
+/**
+ * Operation for the renameCollection command.
+ *
+ * @api
+ * @see \MongoDB\Collection::rename()
+ * @see \MongoDB\Database::renameCollection()
+ * @see https://mongodb.com/docs/manual/reference/command/renameCollection/
+ */
+class RenameCollection implements Executable
+{
+    /** @var string */
+    private $fromNamespace;
+
+    /** @var string */
+    private $toNamespace;
+
+    /** @var array */
+    private $options;
+
+    /**
+     * Constructs a renameCollection command.
+     *
+     * Supported options:
+     *
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
+     *
+     *  * session (MongoDB\Driver\Session): Client session.
+     *
+     *  * typeMap (array): Type map for BSON deserialization. This will be used
+     *    for the returned command result document.
+     *
+     *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
+     *
+     *  * dropTarget (boolean): If true, MongoDB will drop the target before
+     *    renaming the collection.
+     *
+     * @param string $fromDatabaseName   Database name
+     * @param string $fromCollectionName Collection name
+     * @param string $toDatabaseName     New database name
+     * @param string $toCollectionName   New collection name
+     * @param array  $options            Command options
+     * @throws InvalidArgumentException for parameter/option parsing errors
+     */
+    public function __construct(string $fromDatabaseName, string $fromCollectionName, string $toDatabaseName, string $toCollectionName, array $options = [])
+    {
+        if (isset($options['session']) && ! $options['session'] instanceof Session) {
+            throw InvalidArgumentException::invalidType('"session" option', $options['session'], Session::class);
+        }
+
+        if (isset($options['typeMap']) && ! is_array($options['typeMap'])) {
+            throw InvalidArgumentException::invalidType('"typeMap" option', $options['typeMap'], 'array');
+        }
+
+        if (isset($options['writeConcern']) && ! $options['writeConcern'] instanceof WriteConcern) {
+            throw InvalidArgumentException::invalidType('"writeConcern" option', $options['writeConcern'], WriteConcern::class);
+        }
+
+        if (isset($options['writeConcern']) && $options['writeConcern']->isDefault()) {
+            unset($options['writeConcern']);
+        }
+
+        if (isset($options['dropTarget']) && ! is_bool($options['dropTarget'])) {
+            throw InvalidArgumentException::invalidType('"dropTarget" option', $options['dropTarget'], 'boolean');
+        }
+
+        $this->fromNamespace = $fromDatabaseName . '.' . $fromCollectionName;
+        $this->toNamespace = $toDatabaseName . '.' . $toCollectionName;
+        $this->options = $options;
+    }
+
+    /**
+     * Execute the operation.
+     *
+     * @see Executable::execute()
+     * @param Server $server
+     * @return array|object Command result document
+     * @throws UnsupportedException if write concern is used and unsupported
+     * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
+     */
+    public function execute(Server $server)
+    {
+        $inTransaction = isset($this->options['session']) && $this->options['session']->isInTransaction();
+        if ($inTransaction && isset($this->options['writeConcern'])) {
+            throw UnsupportedException::writeConcernNotSupportedInTransaction();
+        }
+
+        $cursor = $server->executeWriteCommand('admin', $this->createCommand(), $this->createOptions());
+
+        if (isset($this->options['typeMap'])) {
+            $cursor->setTypeMap($this->options['typeMap']);
+        }
+
+        return current($cursor->toArray());
+    }
+
+    /**
+     * Create the renameCollection command.
+     *
+     * @return Command
+     */
+    private function createCommand()
+    {
+        $cmd = [
+            'renameCollection' => $this->fromNamespace,
+            'to' => $this->toNamespace,
+        ];
+
+        foreach (['comment', 'dropTarget'] as $option) {
+            if (isset($this->options[$option])) {
+                $cmd[$option] = $this->options[$option];
+            }
+        }
+
+        return new Command($cmd);
+    }
+
+    /**
+     * Create options for executing the command.
+     *
+     * @see https://php.net/manual/en/mongodb-driver-server.executewritecommand.php
+     * @return array
+     */
+    private function createOptions()
+    {
+        $options = [];
+
+        if (isset($this->options['session'])) {
+            $options['session'] = $this->options['session'];
+        }
+
+        if (isset($this->options['writeConcern'])) {
+            $options['writeConcern'] = $this->options['writeConcern'];
+        }
+
+        return $options;
+    }
+}

cache/stores/mongodb/MongoDB/Operation/ReplaceOne.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -22,6 +22,7 @@ use MongoDB\Driver\Server;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
 use MongoDB\UpdateResult;
+
 use function is_array;
 use function is_object;
 use function MongoDB\is_first_key_operator;
@@ -32,7 +33,7 @@ use function MongoDB\is_pipeline;
  *
  * @api
  * @see \MongoDB\Collection::replaceOne()
- * @see http://docs.mongodb.org/manual/reference/command/update/
+ * @see https://mongodb.com/docs/manual/reference/command/update/
  */
 class ReplaceOne implements Executable
 {
@@ -47,13 +48,11 @@ class ReplaceOne implements Executable
      *  * bypassDocumentValidation (boolean): If true, allows the write to
      *    circumvent document level validation.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
-     *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -64,11 +63,14 @@ class ReplaceOne implements Executable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * upsert (boolean): When true, a new document is created if no document
      *    matches the query. The default is false.
      *
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
+     *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
      * @param string       $databaseName   Database name

cache/stores/mongodb/MongoDB/Operation/Update.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -25,12 +25,14 @@ use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
 use MongoDB\UpdateResult;
+
 use function is_array;
 use function is_bool;
 use function is_object;
 use function is_string;
 use function MongoDB\is_first_key_operator;
 use function MongoDB\is_pipeline;
+use function MongoDB\is_write_concern_acknowledged;
 use function MongoDB\server_supports_feature;
 
 /**
@@ -40,21 +42,12 @@ use function MongoDB\server_supports_feature;
  * operation classes.
  *
  * @internal
- * @see http://docs.mongodb.org/manual/reference/command/update/
+ * @see https://mongodb.com/docs/manual/reference/command/update/
  */
 class Update implements Executable, Explainable
 {
     /** @var integer */
-    private static $wireVersionForArrayFilters = 6;
-
-    /** @var integer */
-    private static $wireVersionForCollation = 5;
-
-    /** @var integer */
-    private static $wireVersionForDocumentLevelValidation = 4;
-
-    /** @var integer */
-    private static $wireVersionForHintServerSideError = 5;
+    private static $wireVersionForHint = 8;
 
     /** @var string */
     private $databaseName;
@@ -79,19 +72,14 @@ class Update implements Executable, Explainable
      *  * arrayFilters (document array): A set of filters specifying to which
      *    array elements an update should apply.
      *
-     *    This is not supported for server versions < 3.6 and will result in an
-     *    exception at execution time if used.
-     *
      *  * bypassDocumentValidation (boolean): If true, allows the write to
      *    circumvent document level validation.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
-     *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -106,11 +94,14 @@ class Update implements Executable, Explainable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * upsert (boolean): When true, a new document is created if no document
      *    matches the query. The default is false.
      *
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
+     *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
      * @param string       $databaseName   Database name
@@ -172,6 +163,14 @@ class Update implements Executable, Explainable
             throw InvalidArgumentException::invalidType('"writeConcern" option', $options['writeConcern'], WriteConcern::class);
         }
 
+        if (isset($options['let']) && ! is_array($options['let']) && ! is_object($options['let'])) {
+            throw InvalidArgumentException::invalidType('"let" option', $options['let'], 'array or object');
+        }
+
+        if (isset($options['bypassDocumentValidation']) && ! $options['bypassDocumentValidation']) {
+            unset($options['bypassDocumentValidation']);
+        }
+
         if (isset($options['writeConcern']) && $options['writeConcern']->isDefault()) {
             unset($options['writeConcern']);
         }
@@ -189,23 +188,17 @@ class Update implements Executable, Explainable
      * @see Executable::execute()
      * @param Server $server
      * @return UpdateResult
-     * @throws UnsupportedException if array filters or collation is used and unsupported
+     * @throws UnsupportedException if hint or write concern is used and unsupported
      * @throws DriverRuntimeException for other driver errors (e.g. connection errors)
      */
     public function execute(Server $server)
     {
-        if (isset($this->options['arrayFilters']) && ! server_supports_feature($server, self::$wireVersionForArrayFilters)) {
-            throw UnsupportedException::arrayFiltersNotSupported();
-        }
-
-        if (isset($this->options['collation']) && ! server_supports_feature($server, self::$wireVersionForCollation)) {
-            throw UnsupportedException::collationNotSupported();
-        }
-
-        /* Server versions >= 3.4.0 raise errors for unknown update
-         * options. For previous versions, the CRUD spec requires a client-side
-         * error. */
-        if (isset($this->options['hint']) && ! server_supports_feature($server, self::$wireVersionForHintServerSideError)) {
+        /* CRUD spec requires a client-side error when using "hint" with an
+         * unacknowledged write concern on an unsupported server. */
+        if (
+            isset($this->options['writeConcern']) && ! is_write_concern_acknowledged($this->options['writeConcern']) &&
+            isset($this->options['hint']) && ! server_supports_feature($server, self::$wireVersionForHint)
+        ) {
             throw UnsupportedException::hintNotSupported();
         }
 
@@ -214,15 +207,7 @@ class Update implements Executable, Explainable
             throw UnsupportedException::writeConcernNotSupportedInTransaction();
         }
 
-        $bulkOptions = [];
-
-        if (! empty($this->options['bypassDocumentValidation']) &&
-            server_supports_feature($server, self::$wireVersionForDocumentLevelValidation)
-        ) {
-            $bulkOptions['bypassDocumentValidation'] = $this->options['bypassDocumentValidation'];
-        }
-
-        $bulk = new Bulk($bulkOptions);
+        $bulk = new Bulk($this->createBulkWriteOptions());
         $bulk->update($this->filter, $this->update, $this->createUpdateOptions());
 
         $writeResult = $server->executeBulkWrite($this->databaseName . '.' . $this->collectionName, $bulk, $this->createExecuteOptions());
@@ -230,27 +215,55 @@ class Update implements Executable, Explainable
         return new UpdateResult($writeResult);
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         $cmd = ['update' => $this->collectionName, 'updates' => [['q' => $this->filter, 'u' => $this->update] + $this->createUpdateOptions()]];
 
-        if (isset($this->options['writeConcern'])) {
-            $cmd['writeConcern'] = $this->options['writeConcern'];
+        if (isset($this->options['bypassDocumentValidation'])) {
+            $cmd['bypassDocumentValidation'] = $this->options['bypassDocumentValidation'];
         }
 
-        if (! empty($this->options['bypassDocumentValidation']) &&
-            server_supports_feature($server, self::$wireVersionForDocumentLevelValidation)
-        ) {
-            $cmd['bypassDocumentValidation'] = $this->options['bypassDocumentValidation'];
+        if (isset($this->options['writeConcern'])) {
+            $cmd['writeConcern'] = $this->options['writeConcern'];
         }
 
         return $cmd;
     }
 
+    /**
+     * Create options for constructing the bulk write.
+     *
+     * @see https://php.net/manual/en/mongodb-driver-bulkwrite.construct.php
+     * @return array
+     */
+    private function createBulkWriteOptions()
+    {
+        $options = [];
+
+        foreach (['bypassDocumentValidation', 'comment'] as $option) {
+            if (isset($this->options[$option])) {
+                $options[$option] = $this->options[$option];
+            }
+        }
+
+        if (isset($this->options['let'])) {
+            $options['let'] = (object) $this->options['let'];
+        }
+
+        return $options;
+    }
+
     /**
      * Create options for executing the bulk write.
      *
-     * @see http://php.net/manual/en/mongodb-driver-server.executebulkwrite.php
+     * @see https://php.net/manual/en/mongodb-driver-server.executebulkwrite.php
      * @return array
      */
     private function createExecuteOptions()

cache/stores/mongodb/MongoDB/Operation/UpdateMany.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -22,6 +22,7 @@ use MongoDB\Driver\Server;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
 use MongoDB\UpdateResult;
+
 use function is_array;
 use function is_object;
 use function MongoDB\is_first_key_operator;
@@ -32,7 +33,7 @@ use function MongoDB\is_pipeline;
  *
  * @api
  * @see \MongoDB\Collection::updateMany()
- * @see http://docs.mongodb.org/manual/reference/command/update/
+ * @see https://mongodb.com/docs/manual/reference/command/update/
  */
 class UpdateMany implements Executable, Explainable
 {
@@ -47,19 +48,14 @@ class UpdateMany implements Executable, Explainable
      *  * arrayFilters (document array): A set of filters specifying to which
      *    array elements an update should apply.
      *
-     *    This is not supported for server versions < 3.6 and will result in an$
-     *    exception at execution time if used.
-     *
      *  * bypassDocumentValidation (boolean): If true, allows the write to
      *    circumvent document level validation.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
-     *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -70,11 +66,14 @@ class UpdateMany implements Executable, Explainable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * upsert (boolean): When true, a new document is created if no document
      *    matches the query. The default is false.
      *
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
+     *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
      * @param string       $databaseName   Database name
@@ -117,6 +116,13 @@ class UpdateMany implements Executable, Explainable
         return $this->update->execute($server);
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->update->getCommandDocument($server);

cache/stores/mongodb/MongoDB/Operation/UpdateOne.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -22,6 +22,7 @@ use MongoDB\Driver\Server;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnsupportedException;
 use MongoDB\UpdateResult;
+
 use function is_array;
 use function is_object;
 use function MongoDB\is_first_key_operator;
@@ -32,7 +33,7 @@ use function MongoDB\is_pipeline;
  *
  * @api
  * @see \MongoDB\Collection::updateOne()
- * @see http://docs.mongodb.org/manual/reference/command/update/
+ * @see https://mongodb.com/docs/manual/reference/command/update/
  */
 class UpdateOne implements Executable, Explainable
 {
@@ -47,19 +48,14 @@ class UpdateOne implements Executable, Explainable
      *  * arrayFilters (document array): A set of filters specifying to which
      *    array elements an update should apply.
      *
-     *    This is not supported for server versions < 3.6 and will result in an$
-     *    exception at execution time if used.
-     *
      *  * bypassDocumentValidation (boolean): If true, allows the write to
      *    circumvent document level validation.
      *
-     *    For servers < 3.2, this option is ignored as document level validation
-     *    is not available.
-     *
      *  * collation (document): Collation specification.
      *
-     *    This is not supported for server versions < 3.4 and will result in an
-     *    exception at execution time if used.
+     *  * comment (mixed): BSON value to attach as a comment to this command.
+     *
+     *    This is not supported for servers versions < 4.4.
      *
      *  * hint (string|document): The index to use. Specify either the index
      *    name as a string or the index key pattern as a document. If specified,
@@ -70,11 +66,14 @@ class UpdateOne implements Executable, Explainable
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
-     *
      *  * upsert (boolean): When true, a new document is created if no document
      *    matches the query. The default is false.
      *
+     *  * let (document): Map of parameter names and values. Values must be
+     *    constant or closed expressions that do not reference document fields.
+     *    Parameters can then be accessed as variables in an aggregate
+     *    expression context (e.g. "$$var").
+     *
      *  * writeConcern (MongoDB\Driver\WriteConcern): Write concern.
      *
      * @param string       $databaseName   Database name
@@ -117,6 +116,13 @@ class UpdateOne implements Executable, Explainable
         return $this->update->execute($server);
     }
 
+    /**
+     * Returns the command document for this operation.
+     *
+     * @see Explainable::getCommandDocument()
+     * @param Server $server
+     * @return array
+     */
     public function getCommandDocument(Server $server)
     {
         return $this->update->getCommandDocument($server);

cache/stores/mongodb/MongoDB/Operation/Watch.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2017 MongoDB, Inc.
+ * Copyright 2017-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -32,10 +32,13 @@ use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\UnexpectedValueException;
 use MongoDB\Exception\UnsupportedException;
 use MongoDB\Model\ChangeStreamIterator;
+
 use function array_intersect_key;
+use function array_key_exists;
 use function array_unshift;
 use function count;
 use function is_array;
+use function is_bool;
 use function is_object;
 use function is_string;
 use function MongoDB\Driver\Monitoring\addSubscriber;
@@ -51,12 +54,18 @@ use function MongoDB\server_supports_feature;
  *
  * @api
  * @see \MongoDB\Collection::watch()
- * @see https://docs.mongodb.com/manual/changeStreams/
+ * @see https://mongodb.com/docs/manual/changeStreams/
  */
 class Watch implements Executable, /* @internal */ CommandSubscriber
 {
-    const FULL_DOCUMENT_DEFAULT = 'default';
-    const FULL_DOCUMENT_UPDATE_LOOKUP = 'updateLookup';
+    public const FULL_DOCUMENT_DEFAULT = 'default';
+    public const FULL_DOCUMENT_UPDATE_LOOKUP = 'updateLookup';
+    public const FULL_DOCUMENT_WHEN_AVAILABLE = 'whenAvailable';
+    public const FULL_DOCUMENT_REQUIRED = 'required';
+
+    public const FULL_DOCUMENT_BEFORE_CHANGE_OFF = 'off';
+    public const FULL_DOCUMENT_BEFORE_CHANGE_WHEN_AVAILABLE = 'whenAvailable';
+    public const FULL_DOCUMENT_BEFORE_CHANGE_REQUIRED = 'required';
 
     /** @var integer */
     private static $wireVersionForStartAtOperationTime = 7;
@@ -103,15 +112,37 @@ class Watch implements Executable, /* @internal */ CommandSubscriber
      *
      *  * collation (document): Specifies a collation.
      *
-     *  * fullDocument (string): Determines whether the "fullDocument" field
-     *    will be populated for update operations. By default, change streams
-     *    only return the delta of fields during the update operation (via the
-     *    "updateDescription" field). To additionally return the most current
-     *    majority-committed version of the updated document, specify
-     *    "updateLookup" for this option. Defaults to "default".
+     *  * comment (mixed): BSON value to attach as a comment to this command.
      *
-     *    Insert and replace operations always include the "fullDocument" field
-     *    and delete operations omit the field as the document no longer exists.
+     *    Only string values are supported for server versions < 4.4.
+     *
+     *  * fullDocument (string): Determines how the "fullDocument" response
+     *    field will be populated for update operations.
+     *
+     *    By default, change streams only return the delta of fields (via an
+     *    "updateDescription" field) for update operations and "fullDocument" is
+     *    omitted. Insert and replace operations always include the
+     *    "fullDocument" field. Delete operations omit the field as the document
+     *    no longer exists.
+     *
+     *    Specify "updateLookup" to return the current majority-committed
+     *    version of the updated document.
+     *
+     *    MongoDB 6.0+ allows returning the post-image of the modified document
+     *    if the collection has changeStreamPreAndPostImages enabled. Specify
+     *    "whenAvailable" to return the post-image if available or a null value
+     *    if not. Specify "required" to return the post-image if available or
+     *    raise an error if not.
+     *
+     *  * fullDocumentBeforeChange (string): Determines how the
+     *    "fullDocumentBeforeChange" response field will be populated. By
+     *    default, the field is omitted.
+     *
+     *    MongoDB 6.0+ allows returning the pre-image of the modified document
+     *    if the collection has changeStreamPreAndPostImages enabled. Specify
+     *    "whenAvailable" to return the pre-image if available or a null value
+     *    if not. Specify "required" to return the pre-image if available or
+     *    raise an error if not.
      *
      *  * maxAwaitTimeMS (integer): The maximum amount of time for the server to
      *    wait on new documents to satisfy a change stream query.
@@ -131,7 +162,10 @@ class Watch implements Executable, /* @internal */ CommandSubscriber
      *
      *  * session (MongoDB\Driver\Session): Client session.
      *
-     *    Sessions are not supported for server versions < 3.6.
+     *  * showExpandedEvents (boolean): Enables the server to send the expanded
+     *    list of change stream events.
+     *
+     *    This option is not supported for server versions < 6.0.
      *
      *  * startAfter (document): Specifies the logical starting point for the
      *    new change stream. Unlike "resumeAfter", this option can be used with
@@ -174,14 +208,17 @@ class Watch implements Executable, /* @internal */ CommandSubscriber
         }
 
         $options += [
-            'fullDocument' => self::FULL_DOCUMENT_DEFAULT,
             'readPreference' => new ReadPreference(ReadPreference::RP_PRIMARY),
         ];
 
-        if (! is_string($options['fullDocument'])) {
+        if (array_key_exists('fullDocument', $options) && ! is_string($options['fullDocument'])) {
             throw InvalidArgumentException::invalidType('"fullDocument" option', $options['fullDocument'], 'string');
         }
 
+        if (isset($options['fullDocumentBeforeChange']) && ! is_string($options['fullDocumentBeforeChange'])) {
+            throw InvalidArgumentException::invalidType('"fullDocumentBeforeChange" option', $options['fullDocumentBeforeChange'], 'string');
+        }
+
         if (! $options['readPreference'] instanceof ReadPreference) {
             throw InvalidArgumentException::invalidType('"readPreference" option', $options['readPreference'], ReadPreference::class);
         }
@@ -198,6 +235,10 @@ class Watch implements Executable, /* @internal */ CommandSubscriber
             throw InvalidArgumentException::invalidType('"startAtOperationTime" option', $options['startAtOperationTime'], TimestampInterface::class);
         }
 
+        if (isset($options['showExpandedEvents']) && ! is_bool($options['showExpandedEvents'])) {
+            throw InvalidArgumentException::invalidType('"showExpandedEvents" option', $options['showExpandedEvents'], 'bool');
+        }
+
         /* In the absence of an explicit session, create one to ensure that the
          * initial aggregation and any resume attempts can use the same session
          * ("implicit from the user's perspective" per PHPLIB-342). Since this
@@ -212,8 +253,8 @@ class Watch implements Executable, /* @internal */ CommandSubscriber
             }
         }
 
-        $this->aggregateOptions = array_intersect_key($options, ['batchSize' => 1, 'collation' => 1, 'maxAwaitTimeMS' => 1, 'readConcern' => 1, 'readPreference' => 1, 'session' => 1, 'typeMap' => 1]);
-        $this->changeStreamOptions = array_intersect_key($options, ['fullDocument' => 1, 'resumeAfter' => 1, 'startAfter' => 1, 'startAtOperationTime' => 1]);
+        $this->aggregateOptions = array_intersect_key($options, ['batchSize' => 1, 'collation' => 1, 'comment' => 1, 'maxAwaitTimeMS' => 1, 'readConcern' => 1, 'readPreference' => 1, 'session' => 1, 'typeMap' => 1]);
+        $this->changeStreamOptions = array_intersect_key($options, ['fullDocument' => 1, 'fullDocumentBeforeChange' => 1, 'resumeAfter' => 1, 'showExpandedEvents' => 1, 'startAfter' => 1, 'startAtOperationTime' => 1]);
 
         // Null database name implies a cluster-wide change stream
         if ($databaseName === null) {
@@ -264,8 +305,10 @@ class Watch implements Executable, /* @internal */ CommandSubscriber
             $this->postBatchResumeToken = $reply->cursor->postBatchResumeToken;
         }
 
-        if ($this->shouldCaptureOperationTime($event->getServer()) &&
-            isset($reply->operationTime) && $reply->operationTime instanceof TimestampInterface) {
+        if (
+            $this->shouldCaptureOperationTime($event->getServer()) &&
+            isset($reply->operationTime) && $reply->operationTime instanceof TimestampInterface
+        ) {
             $this->operationTime = $reply->operationTime;
         }
     }
@@ -419,9 +462,11 @@ class Watch implements Executable, /* @internal */ CommandSubscriber
             return false;
         }
 
-        if (isset($this->changeStreamOptions['resumeAfter']) ||
+        if (
+            isset($this->changeStreamOptions['resumeAfter']) ||
             isset($this->changeStreamOptions['startAfter']) ||
-            isset($this->changeStreamOptions['startAtOperationTime'])) {
+            isset($this->changeStreamOptions['startAtOperationTime'])
+        ) {
             return false;
         }
 

cache/stores/mongodb/MongoDB/Operation/WithTransaction.php

@@ -6,6 +6,7 @@ use Exception;
 use MongoDB\Driver\Exception\RuntimeException;
 use MongoDB\Driver\Session;
 use Throwable;
+
 use function call_user_func;
 use function time;
 
@@ -69,7 +70,8 @@ class WithTransaction
                     $session->abortTransaction();
                 }
 
-                if ($e instanceof RuntimeException &&
+                if (
+                    $e instanceof RuntimeException &&
                     $e->hasErrorLabel('TransientTransactionError') &&
                     ! $this->isTransactionTimeLimitExceeded($startTime)
                 ) {
@@ -88,7 +90,8 @@ class WithTransaction
                 try {
                     $session->commitTransaction();
                 } catch (RuntimeException $e) {
-                    if ($e->getCode() !== 50 /* MaxTimeMSExpired */ &&
+                    if (
+                        $e->getCode() !== 50 /* MaxTimeMSExpired */ &&
                         $e->hasErrorLabel('UnknownTransactionCommitResult') &&
                         ! $this->isTransactionTimeLimitExceeded($startTime)
                     ) {
@@ -96,7 +99,8 @@ class WithTransaction
                         continue;
                     }
 
-                    if ($e->hasErrorLabel('TransientTransactionError') &&
+                    if (
+                        $e->hasErrorLabel('TransientTransactionError') &&
                         ! $this->isTransactionTimeLimitExceeded($startTime)
                     ) {
                         // Restart the transaction, invoking the callback again

cache/stores/mongodb/MongoDB/UpdateResult.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,

cache/stores/mongodb/MongoDB/functions.php

@@ -1,12 +1,12 @@
 <?php
 /*
- * Copyright 2015-2017 MongoDB, Inc.
+ * Copyright 2015-present MongoDB, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *   http://www.apache.org/licenses/LICENSE-2.0
+ *   https://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -19,15 +19,19 @@ namespace MongoDB;
 
 use Exception;
 use MongoDB\BSON\Serializable;
+use MongoDB\Driver\Exception\RuntimeException as DriverRuntimeException;
 use MongoDB\Driver\Manager;
 use MongoDB\Driver\ReadPreference;
 use MongoDB\Driver\Server;
 use MongoDB\Driver\Session;
+use MongoDB\Driver\WriteConcern;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\RuntimeException;
+use MongoDB\Operation\ListCollections;
 use MongoDB\Operation\WithTransaction;
 use ReflectionClass;
 use ReflectionException;
+
 use function end;
 use function get_object_vars;
 use function in_array;
@@ -40,6 +44,32 @@ use function MongoDB\BSON\toPHP;
 use function reset;
 use function substr;
 
+/**
+ * Check whether all servers support executing a write stage on a secondary.
+ *
+ * @internal
+ * @param Server[] $servers
+ */
+function all_servers_support_write_stage_on_secondary(array $servers): bool
+{
+    /* Write stages on secondaries are technically supported by FCV 4.4, but the
+     * CRUD spec requires all 5.0+ servers since FCV is not tracked by SDAM. */
+    static $wireVersionForWriteStageOnSecondary = 13;
+
+    foreach ($servers as $server) {
+        // We can assume that load balancers only front 5.0+ servers
+        if ($server->getType() === Server::TYPE_LOAD_BALANCER) {
+            continue;
+        }
+
+        if (! server_supports_feature($server, $wireVersionForWriteStageOnSecondary)) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
 /**
  * Applies a type map to a document.
  *
@@ -71,7 +101,7 @@ function apply_type_map_to_document($document, array $typeMap)
  * @return string
  * @throws InvalidArgumentException
  */
-function generate_index_name($document)
+function generate_index_name($document): string
 {
     if ($document instanceof Serializable) {
         $document = $document->bsonSerialize();
@@ -94,6 +124,53 @@ function generate_index_name($document)
     return $name;
 }
 
+/**
+ * Return a collection's encryptedFields from the encryptedFieldsMap
+ * autoEncryption driver option (if available).
+ *
+ * @internal
+ * @see https://github.com/mongodb/specifications/blob/master/source/client-side-encryption/client-side-encryption.rst#drop-collection-helper
+ * @see Collection::drop
+ * @see Database::createCollection
+ * @see Database::dropCollection
+ * @return array|object|null
+ */
+function get_encrypted_fields_from_driver(string $databaseName, string $collectionName, Manager $manager)
+{
+    $encryptedFieldsMap = (array) $manager->getEncryptedFieldsMap();
+
+    return $encryptedFieldsMap[$databaseName . '.' . $collectionName] ?? null;
+}
+
+/**
+ * Return a collection's encryptedFields option from the server (if any).
+ *
+ * @internal
+ * @see https://github.com/mongodb/specifications/blob/master/source/client-side-encryption/client-side-encryption.rst#drop-collection-helper
+ * @see Collection::drop
+ * @see Database::dropCollection
+ * @return array|object|null
+ */
+function get_encrypted_fields_from_server(string $databaseName, string $collectionName, Manager $manager, Server $server)
+{
+    // No-op if the encryptedFieldsMap autoEncryption driver option was omitted
+    if ($manager->getEncryptedFieldsMap() === null) {
+        return null;
+    }
+
+    $collectionInfoIterator = (new ListCollections($databaseName, ['filter' => ['name' => $collectionName]]))->execute($server);
+
+    foreach ($collectionInfoIterator as $collectionInfo) {
+        /* Note: ListCollections applies a typeMap that converts BSON documents
+         * to PHP arrays. This should not be problematic as encryptedFields here
+         * is only used by drop helpers to obtain names of supporting encryption
+         * collections. */
+        return $collectionInfo['options']['encryptedFields'] ?? null;
+    }
+
+    return null;
+}
+
 /**
  * Return whether the first key in the document starts with a "$" character.
  *
@@ -104,7 +181,7 @@ function generate_index_name($document)
  * @return boolean
  * @throws InvalidArgumentException
  */
-function is_first_key_operator($document)
+function is_first_key_operator($document): bool
 {
     if ($document instanceof Serializable) {
         $document = $document->bsonSerialize();
@@ -131,7 +208,7 @@ function is_first_key_operator($document)
  * @param mixed $pipeline
  * @return boolean
  */
-function is_pipeline($pipeline)
+function is_pipeline($pipeline): bool
 {
     if (! is_array($pipeline)) {
         return false;
@@ -172,7 +249,7 @@ function is_pipeline($pipeline)
  * @param array $options Command options
  * @return boolean
  */
-function is_in_transaction(array $options)
+function is_in_transaction(array $options): bool
 {
     if (isset($options['session']) && $options['session'] instanceof Session && $options['session']->isInTransaction()) {
         return true;
@@ -191,7 +268,7 @@ function is_in_transaction(array $options)
  * @param array $pipeline List of pipeline operations
  * @return boolean
  */
-function is_last_pipeline_operator_write(array $pipeline)
+function is_last_pipeline_operator_write(array $pipeline): bool
 {
     $lastOp = end($pipeline);
 
@@ -210,12 +287,12 @@ function is_last_pipeline_operator_write(array $pipeline)
  * This is used to determine if a mapReduce command requires a primary.
  *
  * @internal
- * @see https://docs.mongodb.com/manual/reference/command/mapReduce/#output-inline
+ * @see https://mongodb.com/docs/manual/reference/command/mapReduce/#output-inline
  * @param string|array|object $out Output specification
  * @return boolean
  * @throws InvalidArgumentException
  */
-function is_mapreduce_output_inline($out)
+function is_mapreduce_output_inline($out): bool
 {
     if (! is_array($out) && ! is_object($out)) {
         return false;
@@ -238,6 +315,25 @@ function is_mapreduce_output_inline($out)
     return key($out) === 'inline';
 }
 
+/**
+ * Return whether the write concern is acknowledged.
+ *
+ * This function is similar to mongoc_write_concern_is_acknowledged but does not
+ * check the fsync option since that was never supported in the PHP driver.
+ *
+ * @internal
+ * @see https://mongodb.com/docs/manual/reference/write-concern/
+ * @param WriteConcern $writeConcern
+ * @return boolean
+ */
+function is_write_concern_acknowledged(WriteConcern $writeConcern): bool
+{
+    /* Note: -1 corresponds to MONGOC_WRITE_CONCERN_W_ERRORS_IGNORED, which is
+     * deprecated synonym of MONGOC_WRITE_CONCERN_W_UNACKNOWLEDGED and slated
+     * for removal in libmongoc 2.0. */
+    return ($writeConcern->getW() !== 0 && $writeConcern->getW() !== -1) || $writeConcern->getJournal() === true;
+}
+
 /**
  * Return whether the server supports a particular feature.
  *
@@ -246,7 +342,7 @@ function is_mapreduce_output_inline($out)
  * @param integer $feature Feature constant (i.e. wire protocol version)
  * @return boolean
  */
-function server_supports_feature(Server $server, $feature)
+function server_supports_feature(Server $server, int $feature): bool
 {
     $info = $server->getInfo();
     $maxWireVersion = isset($info['maxWireVersion']) ? (integer) $info['maxWireVersion'] : 0;
@@ -255,11 +351,19 @@ function server_supports_feature(Server $server, $feature)
     return $minWireVersion <= $feature && $maxWireVersion >= $feature;
 }
 
-function is_string_array($input)
+/**
+ * Return whether the input is an array of strings.
+ *
+ * @internal
+ * @param mixed $input
+ * @return boolean
+ */
+function is_string_array($input): bool
 {
     if (! is_array($input)) {
         return false;
     }
+
     foreach ($input as $item) {
         if (! is_string($item)) {
             return false;
@@ -315,7 +419,7 @@ function recursive_copy($element)
  * @param string $fieldPath The field path to apply the root type to
  * @return array
  */
-function create_field_path_type_map(array $typeMap, $fieldPath)
+function create_field_path_type_map(array $typeMap, string $fieldPath): array
 {
     // If some field paths already exist, we prefix them with the field path we are assuming as the new root
     if (isset($typeMap['fieldPaths']) && is_array($typeMap['fieldPaths'])) {
@@ -383,7 +487,7 @@ function with_transaction(Session $session, callable $callback, array $transacti
  * @param array $options
  * @return Session|null
  */
-function extract_session_from_options(array $options)
+function extract_session_from_options(array $options): ?Session
 {
     if (! isset($options['session']) || ! $options['session'] instanceof Session) {
         return null;
@@ -399,7 +503,7 @@ function extract_session_from_options(array $options)
  * @param array $options
  * @return ReadPreference|null
  */
-function extract_read_preference_from_options(array $options)
+function extract_read_preference_from_options(array $options): ?ReadPreference
 {
     if (! isset($options['readPreference']) || ! $options['readPreference'] instanceof ReadPreference) {
         return null;
@@ -415,7 +519,7 @@ function extract_read_preference_from_options(array $options)
  * @internal
  * @return Server
  */
-function select_server(Manager $manager, array $options)
+function select_server(Manager $manager, array $options): Server
 {
     $session = extract_session_from_options($options);
     if ($session instanceof Session && $session->getServer() !== null) {
@@ -430,3 +534,49 @@ function select_server(Manager $manager, array $options)
 
     return $manager->selectServer($readPreference);
 }
+
+/**
+ * Performs server selection for an aggregate operation with a write stage. The
+ * $options parameter may be modified by reference if a primary read preference
+ * must be forced due to the existence of pre-5.0 servers in the topology.
+ *
+ * @internal
+ * @see https://github.com/mongodb/specifications/blob/master/source/crud/crud.rst#aggregation-pipelines-with-write-stages
+ */
+function select_server_for_aggregate_write_stage(Manager $manager, array &$options): Server
+{
+    $readPreference = extract_read_preference_from_options($options);
+
+    /* If there is either no read preference or a primary read preference, there
+     * is no special server selection logic to apply. */
+    if ($readPreference === null || $readPreference->getMode() === ReadPreference::RP_PRIMARY) {
+        return select_server($manager, $options);
+    }
+
+    $server = null;
+    $serverSelectionError = null;
+
+    try {
+        $server = select_server($manager, $options);
+    } catch (DriverRuntimeException $serverSelectionError) {
+    }
+
+    /* If any pre-5.0 servers exist in the topology, force a primary read
+     * preference and repeat server selection if it previously failed or
+     * selected a secondary. */
+    if (! all_servers_support_write_stage_on_secondary($manager->getServers())) {
+        $options['readPreference'] = new ReadPreference(ReadPreference::RP_PRIMARY);
+
+        if ($server === null || $server->isSecondary()) {
+            return select_server($manager, $options);
+        }
+    }
+
+    /* If the topology only contains 5.0+ servers, we should either return the
+     * previously selected server or propagate the server selection error. */
+    if ($serverSelectionError !== null) {
+        throw $serverSelectionError;
+    }
+
+    return $server;
+}