From cd3557e64c3fe830b7384ce1a093e8a7ae1ac28b Mon Sep 17 00:00:00 2001
From: Tim Hunt <T.J.Hunt@open.ac.uk>
Date: Wed, 16 Mar 2011 16:28:48 +0000
Subject: [PATCH] MDL-20636 Essay question type, make is_same_response consider
 files. #216

---
 question/engine/datalib.php      | 37 ++++++++++++++++++++++++++++++--
 question/engine/lib.php          |  9 --------
 question/type/essay/question.php |  4 +++-
 3 files changed, 38 insertions(+), 12 deletions(-)

diff --git a/question/engine/datalib.php b/question/engine/datalib.php
index b4fe3a63989..2a7e526f925 100644
--- a/question/engine/datalib.php
+++ b/question/engine/datalib.php
@@ -954,6 +954,12 @@ class question_file_saver {
     /** @var string the file area name. */
     protected $filearea;
 
+    /**
+     * @var string the value to store in the question_attempt_step_data to
+     * represent these files.
+     */
+    protected $value = null;
+
     /**
      * Constuctor.
      * @param int $draftitemid the draft area to save the files from.
@@ -966,9 +972,36 @@ class question_file_saver {
         $this->filearea = $filearea;
     }
 
+    protected function get_value() {
+        global $USER;
+
+        if (!is_null($this->value)) {
+            return $this->value;
+        }
+
+        $fs = get_file_storage();
+        $usercontext = get_context_instance(CONTEXT_USER, $USER->id);
+
+        $files = $fs->get_area_files($usercontext->id, 'user', 'draft',
+                $this->draftitemid, 'sortorder, filepath, filename', false);
+
+        $string = '';
+        foreach ($files as $file) {
+            $string .= $file->get_filepath() . $file->get_filename() . '|' .
+                    $file->get_contenthash() . '|';
+        }
+
+        if ($string) {
+            $this->value = md5($string);
+        } else {
+            $this->value = '';
+        }
+
+        return $this->value;
+    }
+
     public function __toString() {
-        // When stored in the database, we want this value to appear as 1.
-        return '1';
+        return $this->get_value();
     }
 
     /**
diff --git a/question/engine/lib.php b/question/engine/lib.php
index c1c8048e29f..8dbc13a340f 100644
--- a/question/engine/lib.php
+++ b/question/engine/lib.php
@@ -2086,8 +2086,6 @@ class question_attempt {
      *      behaves as if there were no files.
      */
     protected function process_response_files($name, $postdata = null) {
-        global $USER;
-
         if ($postdata) {
             // There can be no files with test data (at the moment).
             return null;
@@ -2098,13 +2096,6 @@ class question_attempt {
             return null;
         }
 
-        $fs = get_file_storage();
-        $usercontext = get_context_instance(CONTEXT_USER, $USER->id);
-
-        if ($fs->is_area_empty($usercontext->id, 'user', 'draft', $draftitemid)) {
-            return null;
-        }
-
         return new question_file_saver($draftitemid, 'question', 'response_' .
                 str_replace($this->get_field_prefix(), '', $name));
     }
diff --git a/question/type/essay/question.php b/question/type/essay/question.php
index 176aec91acd..436cc1d9738 100644
--- a/question/type/essay/question.php
+++ b/question/type/essay/question.php
@@ -82,7 +82,9 @@ class qtype_essay_question extends question_with_responses {
 
     public function is_same_response(array $prevresponse, array $newresponse) {
         return question_utils::arrays_same_at_key_missing_is_blank(
-                $prevresponse, $newresponse, 'answer');
+                $prevresponse, $newresponse, 'answer') && ($this->attachments == 0 ||
+                question_utils::arrays_same_at_key_missing_is_blank(
+                $prevresponse, $newresponse, 'attachments'));
     }
 
     public function check_file_access($qa, $options, $component, $filearea, $args, $forcedownload) {