From 449c835fe2edc8fc62ab7009ecf601f9bed5f258 Mon Sep 17 00:00:00 2001
From: Mikhail Golenkov <mikhailgolenkov@catalyst-au.net>
Date: Tue, 22 Dec 2020 12:57:17 +1100
Subject: [PATCH] MDL-70520 mod_assign: Use task API to get scheduled task
 lastruntime

---
 mod/assign/locallib.php            |  3 +-
 mod/assign/tests/locallib_test.php | 50 ++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/mod/assign/locallib.php b/mod/assign/locallib.php
index 825b7087361..08b0fb0a7d4 100644
--- a/mod/assign/locallib.php
+++ b/mod/assign/locallib.php
@@ -2539,7 +2539,8 @@ class assign {
         // Only ever send a max of one days worth of updates.
         $yesterday = time() - (24 * 3600);
         $timenow   = time();
-        $lastruntime = $DB->get_field('task_scheduled', 'lastruntime', array('component' => 'mod_assign'));
+        $task = \core\task\manager::get_scheduled_task(mod_assign\task\cron_task::class);
+        $lastruntime = $task->get_last_run_time();
 
         // Collect all submissions that require mailing.
         // Submissions are included if all are true:
diff --git a/mod/assign/tests/locallib_test.php b/mod/assign/tests/locallib_test.php
index 31c65ac483e..c62326926df 100644
--- a/mod/assign/tests/locallib_test.php
+++ b/mod/assign/tests/locallib_test.php
@@ -4201,4 +4201,54 @@ Anchor link 2:<a title=\"bananas\" href=\"../logo-240x60.gif\">Link text</a>
         $output3 .= $assign->get_renderer()->render($summary);
         $this->assertContains('Friday, 7 June 2019, 5:37 PM', $output3, '', true);
     }
+
+    /**
+     * Test that cron task uses task API to get its last run time.
+     */
+    public function test_cron_use_task_api_to_get_lastruntime() {
+        global $DB;
+        $this->resetAfterTest();
+        $course = $this->getDataGenerator()->create_course();
+
+        // Create an assignment which allows submissions from 3 days ago.
+        $assign1 = $this->create_instance($course, [
+            'duedate' => time() + DAYSECS,
+            'alwaysshowdescription' => 0,
+            'allowsubmissionsfromdate' => time() - 3 * DAYSECS,
+            'intro' => 'This one should not be re-created',
+        ]);
+
+        // Create an assignment which allows submissions from 1 day ago.
+        $assign2 = $this->create_instance($course, [
+            'duedate' => time() + DAYSECS,
+            'alwaysshowdescription' => 0,
+            'allowsubmissionsfromdate' => time() - DAYSECS,
+            'intro' => 'This one should be re-created',
+        ]);
+
+        // Set last run time 2 days ago.
+        $DB->set_field('task_scheduled', 'lastruntime', time() - 2 * DAYSECS, ['classname' => '\mod_assign\task\cron_task']);
+
+        // Remove events to make sure cron will update calendar and re-create one of them.
+        $params = array('modulename' => 'assign', 'instance' => $assign1->get_instance()->id);
+        $DB->delete_records('event', $params);
+        $params = array('modulename' => 'assign', 'instance' => $assign2->get_instance()->id);
+        $DB->delete_records('event', $params);
+
+        // Run cron.
+        assign::cron();
+
+        // Assert that calendar hasn't been updated for the first assignment as it's supposed to be
+        // updated as part of previous cron runs (allowsubmissionsfromdate is less than lastruntime).
+        $params = array('modulename' => 'assign', 'instance' => $assign1->get_instance()->id);
+        $event1 = $DB->get_record('event', $params);
+        $this->assertEmpty($event1);
+
+        // Assert that calendar has been updated for the second assignment
+        // because its allowsubmissionsfromdate is greater than lastruntime.
+        $params = array('modulename' => 'assign', 'instance' => $assign2->get_instance()->id);
+        $event2 = $DB->get_record('event', $params);
+        $this->assertNotEmpty($event2);
+        $this->assertSame('This one should be re-created', $event2->description);
+    }
 }