MDL-40081 completion: clean up criteria records for deleted courses.

lib/tests/completionlib_test.php

@@ -875,6 +875,44 @@ class core_completionlib_testcase extends advanced_testcase {
         $this->assertFalse($c2->has_activities());
     }
 
+    /**
+     * Test that data is cleaned up when we delete courses that are set as completion criteria for other courses
+     *
+     * @return void
+     */
+    public function test_course_delete_prerequisite() {
+        global $DB;
+
+        $this->setup_data();
+
+        $courseprerequisite = $this->getDataGenerator()->create_course(['enablecompletion' => true]);
+
+        $criteriadata = (object) [
+            'id' => $this->course->id,
+            'criteria_course' => [$courseprerequisite->id],
+        ];
+
+        /** @var completion_criteria_course $criteria */
+        $criteria = completion_criteria::factory(['criteriatype' => COMPLETION_CRITERIA_TYPE_COURSE]);
+        $criteria->update_config($criteriadata);
+
+        // Sanity test.
+        $this->assertTrue($DB->record_exists('course_completion_criteria', [
+            'course' => $this->course->id,
+            'criteriatype' => COMPLETION_CRITERIA_TYPE_COURSE,
+            'courseinstance' => $courseprerequisite->id,
+        ]));
+
+        // Deleting the prerequisite course should remove the completion criteria.
+        delete_course($courseprerequisite, false);
+
+        $this->assertFalse($DB->record_exists('course_completion_criteria', [
+            'course' => $this->course->id,
+            'criteriatype' => COMPLETION_CRITERIA_TYPE_COURSE,
+            'courseinstance' => $courseprerequisite->id,
+        ]));
+    }
+
     /**
      * Test course module completion update event.
      */