diff --git a/admin/tool/dataprivacy/tests/api_test.php b/admin/tool/dataprivacy/tests/api_test.php
index 24db193b258..8e414094744 100644
--- a/admin/tool/dataprivacy/tests/api_test.php
+++ b/admin/tool/dataprivacy/tests/api_test.php
@@ -237,9 +237,9 @@ class tool_dataprivacy_api_testcase extends advanced_testcase {
         // There should only be one PO role.
         $this->assertCount(1, $roleids);
         // Confirm it contains the manager role.
-        $this->assertContains($managerroleid, $roleids);
+        $this->assertContainsEquals($managerroleid, $roleids);
         // And it does not contain the editing teacher role.
-        $this->assertNotContains($editingteacherroleid, $roleids);
+        $this->assertNotContainsEquals($editingteacherroleid, $roleids);
     }
 
     /**
@@ -838,7 +838,7 @@ class tool_dataprivacy_api_testcase extends advanced_testcase {
             $this->assertCount($filteredcount, $filteredrequests);
             // Confirm the filtered requests match the status filter(s).
             foreach ($filteredrequests as $request) {
-                $this->assertContains($request->get('status'), $statuses);
+                $this->assertContainsEquals($request->get('status'), $statuses);
             }
 
             if ($numstatus > 1) {
diff --git a/admin/tool/dataprivacy/tests/expired_contexts_test.php b/admin/tool/dataprivacy/tests/expired_contexts_test.php
index 6deb9192b81..6a47ae41f88 100644
--- a/admin/tool/dataprivacy/tests/expired_contexts_test.php
+++ b/admin/tool/dataprivacy/tests/expired_contexts_test.php
@@ -950,8 +950,8 @@ class tool_dataprivacy_expired_contexts_testcase extends advanced_testcase {
                 $forumlist = $userlist->get_userlist_for_component('mod_forum');
                 $userids = $forumlist->get_userids();
                 $this->assertCount(1, $userids);
-                $this->assertContains($student->id, $userids);
-                $this->assertNotContains($teacher->id, $userids);
+                $this->assertContainsEquals($student->id, $userids);
+                $this->assertNotContainsEquals($teacher->id, $userids);
                 return true;
             }));
 
@@ -1038,8 +1038,8 @@ class tool_dataprivacy_expired_contexts_testcase extends advanced_testcase {
                 $forumlist = $userlist->get_userlist_for_component('mod_forum');
                 $userids = $forumlist->get_userids();
                 $this->assertCount(1, $userids);
-                $this->assertContains($student->id, $userids);
-                $this->assertNotContains($teacher->id, $userids);
+                $this->assertContainsEquals($student->id, $userids);
+                $this->assertNotContainsEquals($teacher->id, $userids);
                 return true;
             }));
 
@@ -1127,8 +1127,8 @@ class tool_dataprivacy_expired_contexts_testcase extends advanced_testcase {
                 $forumlist = $userlist->get_userlist_for_component('mod_forum');
                 $userids = $forumlist->get_userids();
                 $this->assertCount(1, $userids);
-                $this->assertContains($student->id, $userids);
-                $this->assertNotContains($teacher->id, $userids);
+                $this->assertContainsEquals($student->id, $userids);
+                $this->assertNotContainsEquals($teacher->id, $userids);
                 return true;
             }));
 
@@ -1223,8 +1223,8 @@ class tool_dataprivacy_expired_contexts_testcase extends advanced_testcase {
                 $forumlist = $userlist->get_userlist_for_component('mod_forum');
                 $userids = $forumlist->get_userids();
                 $this->assertCount(2, $userids);
-                $this->assertContains($student->id, $userids);
-                $this->assertContains($teacher->id, $userids);
+                $this->assertContainsEquals($student->id, $userids);
+                $this->assertContainsEquals($teacher->id, $userids);
                 return true;
             }));
 
diff --git a/analytics/tests/prediction_test.php b/analytics/tests/prediction_test.php
index 159bfd83466..0fac8189714 100644
--- a/analytics/tests/prediction_test.php
+++ b/analytics/tests/prediction_test.php
@@ -261,8 +261,8 @@ class core_analytics_prediction_testcase extends advanced_testcase {
             $this->assertEquals($predictedrangeindex, $predictedrange->rangeindex);
             $sampleids = json_decode($predictedrange->sampleids, true);
             $this->assertCount(2, $sampleids);
-            $this->assertContains($course1->id, $sampleids);
-            $this->assertContains($course2->id, $sampleids);
+            $this->assertContainsEquals($course1->id, $sampleids);
+            $this->assertContainsEquals($course2->id, $sampleids);
         }
         $this->assertEquals(1, $DB->count_records('analytics_used_files',
             array('modelid' => $model->get_id(), 'action' => 'predicted')));
@@ -302,10 +302,10 @@ class core_analytics_prediction_testcase extends advanced_testcase {
             $this->assertEquals($predictedrangeindex, $predictedrange->rangeindex);
             $sampleids = json_decode($predictedrange->sampleids, true);
             $this->assertCount(4, $sampleids);
-            $this->assertContains($course1->id, $sampleids);
-            $this->assertContains($course2->id, $sampleids);
-            $this->assertContains($course3->id, $sampleids);
-            $this->assertContains($course4->id, $sampleids);
+            $this->assertContainsEquals($course1->id, $sampleids);
+            $this->assertContainsEquals($course2->id, $sampleids);
+            $this->assertContainsEquals($course3->id, $sampleids);
+            $this->assertContainsEquals($course4->id, $sampleids);
         }
         $this->assertEquals(2, $DB->count_records('analytics_used_files',
             array('modelid' => $model->get_id(), 'action' => 'predicted')));
diff --git a/blog/tests/privacy_test.php b/blog/tests/privacy_test.php
index 5eab70b7816..dcb712a8b5b 100644
--- a/blog/tests/privacy_test.php
+++ b/blog/tests/privacy_test.php
@@ -388,7 +388,7 @@ class core_blog_privacy_testcase extends provider_testcase {
 
         // Generate list of contexts for user.
         $contexts = provider::get_contexts_for_userid($user->id);
-        $this->assertContains($context->id, $contexts->get_contextids());
+        $this->assertContainsEquals($context->id, $contexts->get_contextids());
 
         // Now delete the blog entry.
         $entry->delete();
diff --git a/calendar/tests/rrule_manager_test.php b/calendar/tests/rrule_manager_test.php
index 3af4655cb8c..3f21be30362 100644
--- a/calendar/tests/rrule_manager_test.php
+++ b/calendar/tests/rrule_manager_test.php
@@ -2437,7 +2437,7 @@ class core_calendar_rrule_manager_testcase extends advanced_testcase {
             $this->assertEquals($expecteddate->format('Y-m-d H:i:s'), date('Y-m-d H:i:s', $record->timestart));
 
             // Assert that the record is either the 7th, 8th, 9th, ... 13th day of the month.
-            $this->assertContains(date('j', $record->timestart), $bymonthdays);
+            $this->assertContainsEquals(date('j', $record->timestart), $bymonthdays);
         }
     }
 
@@ -2494,7 +2494,7 @@ class core_calendar_rrule_manager_testcase extends advanced_testcase {
             $this->assertEquals($expecteddate->format('Y-m-d H:i:s'), date('Y-m-d H:i:s', $record->timestart));
 
             // Assert that the record is either the 2nd, 3rd, 4th ... 8th day of the month.
-            $this->assertContains(date('j', $record->timestart), $bymonthdays);
+            $this->assertContainsEquals(date('j', $record->timestart), $bymonthdays);
         }
     }
 
@@ -2525,7 +2525,7 @@ class core_calendar_rrule_manager_testcase extends advanced_testcase {
             (new DateTime('1997-11-06 09:00:00 EST'))->getTimestamp()
         ];
         foreach ($records as $record) {
-            $this->assertContains($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
+            $this->assertContainsEquals($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
         }
     }
 
@@ -2603,7 +2603,7 @@ class core_calendar_rrule_manager_testcase extends advanced_testcase {
             (new DateTime('1997-09-02 15:00:00 EDT'))->getTimestamp(),
         ];
         foreach ($records as $record) {
-            $this->assertContains($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
+            $this->assertContainsEquals($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
         }
     }
 
@@ -2634,7 +2634,7 @@ class core_calendar_rrule_manager_testcase extends advanced_testcase {
             (new DateTime('1997-09-02 10:15:00 EDT'))->getTimestamp(),
         ];
         foreach ($records as $record) {
-            $this->assertContains($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
+            $this->assertContainsEquals($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
         }
     }
 
@@ -2663,7 +2663,7 @@ class core_calendar_rrule_manager_testcase extends advanced_testcase {
             (new DateTime('1997-09-02 13:30:00 EDT'))->getTimestamp(),
         ];
         foreach ($records as $record) {
-            $this->assertContains($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
+            $this->assertContainsEquals($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
         }
     }
 
@@ -2707,7 +2707,7 @@ class core_calendar_rrule_manager_testcase extends advanced_testcase {
         $this->assertCount($count, $records);
 
         foreach ($records as $record) {
-            $this->assertContains($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
+            $this->assertContainsEquals($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
         }
     }
 
@@ -2751,7 +2751,7 @@ class core_calendar_rrule_manager_testcase extends advanced_testcase {
         $this->assertCount($count, $records);
 
         foreach ($records as $record) {
-            $this->assertContains($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
+            $this->assertContainsEquals($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
         }
     }
 
@@ -2782,7 +2782,7 @@ class core_calendar_rrule_manager_testcase extends advanced_testcase {
             (new DateTime('1997-08-24 09:00:00 EDT'))->getTimestamp(),
         ];
         foreach ($records as $record) {
-            $this->assertContains($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
+            $this->assertContainsEquals($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
         }
     }
 
@@ -2815,7 +2815,7 @@ class core_calendar_rrule_manager_testcase extends advanced_testcase {
         ];
 
         foreach ($records as $record) {
-            $this->assertContains($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
+            $this->assertContainsEquals($record->timestart, $expecteddates, date('Y-m-d H:i:s', $record->timestart) . ' is not found.');
         }
     }
 
diff --git a/cohort/tests/privacy_test.php b/cohort/tests/privacy_test.php
index c6c04bc9a72..43fc0d25d5c 100644
--- a/cohort/tests/privacy_test.php
+++ b/cohort/tests/privacy_test.php
@@ -71,8 +71,8 @@ class core_cohort_testcase extends provider_testcase {
         // User is member of 2 cohorts.
         $contextlist = provider::get_contexts_for_userid($user->id);
         $this->assertCount(2, (array) $contextlist->get_contextids());
-        $this->assertContains($coursecategoryctx->id, $contextlist->get_contextids());
-        $this->assertContains($systemctx->id, $contextlist->get_contextids());
+        $this->assertContainsEquals($coursecategoryctx->id, $contextlist->get_contextids());
+        $this->assertContainsEquals($systemctx->id, $contextlist->get_contextids());
     }
 
     /**
diff --git a/competency/tests/api_test.php b/competency/tests/api_test.php
index df77dd47e85..d6d4f7cfda3 100644
--- a/competency/tests/api_test.php
+++ b/competency/tests/api_test.php
@@ -4395,7 +4395,7 @@ class core_competency_api_testcase extends advanced_testcase {
         $leastarray = array($comp4->get('id'), $comp6->get('id'));
         foreach ($result as $one) {
             $this->assertInstanceOf('\core_competency\competency', $one);
-            $this->assertContains($one->get('id'), $leastarray);
+            $this->assertContainsEquals($one->get('id'), $leastarray);
         }
     }
 
diff --git a/contentbank/tests/privacy_test.php b/contentbank/tests/privacy_test.php
index 3717d40474b..63847d6d650 100644
--- a/contentbank/tests/privacy_test.php
+++ b/contentbank/tests/privacy_test.php
@@ -68,10 +68,10 @@ class core_contentbank_privacy_testcase extends provider_testcase {
         $contextlistids = $contextlist->get_contextids();
         $this->assertCount(3, $contextlistids);
         // Check the list against the expected list of contexts.
-        $this->assertContains($scenario->systemcontext->id, $contextlistids);
-        $this->assertContains($scenario->coursecategorycontext->id,
+        $this->assertContainsEquals($scenario->systemcontext->id, $contextlistids);
+        $this->assertContainsEquals($scenario->coursecategorycontext->id,
             $contextlistids);
-        $this->assertContains($scenario->coursecontext->id, $contextlistids);
+        $this->assertContainsEquals($scenario->coursecontext->id, $contextlistids);
 
         // Testing againts Teacher who has content in the one context.
         $contextlist = provider::get_contexts_for_userid($scenario->teacher->id);
@@ -79,10 +79,10 @@ class core_contentbank_privacy_testcase extends provider_testcase {
         $contextlistids = $contextlist->get_contextids();
         $this->assertCount(1, $contextlistids);
         // Check the againts Course Context.
-        $this->assertContains($scenario->coursecontext->id, $contextlistids);
+        $this->assertContainsEquals($scenario->coursecontext->id, $contextlistids);
         // And there is not a System and Course Category Context.
-        $this->assertNotContains($scenario->systemcontext->id, $contextlistids);
-        $this->assertNotContains($scenario->coursecategorycontext->id, $contextlistids);
+        $this->assertNotContainsEquals($scenario->systemcontext->id, $contextlistids);
+        $this->assertNotContainsEquals($scenario->coursecategorycontext->id, $contextlistids);
     }
 
     /**
diff --git a/course/tests/courselib_test.php b/course/tests/courselib_test.php
index 886aeadcedd..05a3b6050ea 100644
--- a/course/tests/courselib_test.php
+++ b/course/tests/courselib_test.php
@@ -1517,9 +1517,9 @@ class core_course_courselib_testcase extends advanced_testcase {
         $modinfo = get_fast_modinfo($course);
 
         // Verify that forum and page have been moved to the hidden section and quiz has not.
-        $this->assertContains($forum->cmid, $modinfo->sections[3]);
-        $this->assertContains($page->cmid, $modinfo->sections[3]);
-        $this->assertNotContains($quiz->cmid, $modinfo->sections[3]);
+        $this->assertContainsEquals($forum->cmid, $modinfo->sections[3]);
+        $this->assertContainsEquals($page->cmid, $modinfo->sections[3]);
+        $this->assertNotContainsEquals($quiz->cmid, $modinfo->sections[3]);
 
         // Verify that forum has been made invisible.
         $forumcm = $modinfo->cms[$forum->cmid];
diff --git a/enrol/flatfile/tests/privacy_provider_test.php b/enrol/flatfile/tests/privacy_provider_test.php
index 7c9f22d5b0e..31a495d22ef 100644
--- a/enrol/flatfile/tests/privacy_provider_test.php
+++ b/enrol/flatfile/tests/privacy_provider_test.php
@@ -92,14 +92,14 @@ class enrol_flatfile_privacy_testcase extends provider_testcase {
         $contextlist = provider::get_contexts_for_userid($this->user1->id);
         $this->assertEquals(2, $contextlist->count());
         $contextids = $contextlist->get_contextids();
-        $this->assertContains($this->coursecontext1->id, $contextids);
-        $this->assertContains($this->coursecontext3->id, $contextids);
+        $this->assertContainsEquals($this->coursecontext1->id, $contextids);
+        $this->assertContainsEquals($this->coursecontext3->id, $contextids);
 
         // And 1 for user2 on course2.
         $contextlist = provider::get_contexts_for_userid($this->user2->id);
         $this->assertEquals(1, $contextlist->count());
         $contextids = $contextlist->get_contextids();
-        $this->assertContains($this->coursecontext2->id, $contextids);
+        $this->assertContainsEquals($this->coursecontext2->id, $contextids);
     }
 
     /**
@@ -189,8 +189,8 @@ class enrol_flatfile_privacy_testcase extends provider_testcase {
         $contextlist = provider::get_contexts_for_userid($this->user1->id);
         $this->assertEquals(2, $contextlist->count());
         $contextids = $contextlist->get_contextids();
-        $this->assertContains($this->coursecontext1->id, $contextids);
-        $this->assertContains($this->coursecontext3->id, $contextids);
+        $this->assertContainsEquals($this->coursecontext1->id, $contextids);
+        $this->assertContainsEquals($this->coursecontext3->id, $contextids);
 
         $approvedcontextlist = new approved_contextlist(
             $this->user1,
diff --git a/enrol/paypal/tests/privacy_provider_test.php b/enrol/paypal/tests/privacy_provider_test.php
index 391a7d9cf2d..2e886a052ef 100644
--- a/enrol/paypal/tests/privacy_provider_test.php
+++ b/enrol/paypal/tests/privacy_provider_test.php
@@ -263,8 +263,8 @@ class enrol_paypal_privacy_provider_testcase extends \core_privacy\tests\provide
         $this->assertCount(2, $contextlist);
 
         $contextids = $contextlist->get_contextids();
-        $this->assertContains($coursecontext1->id, $contextids);
-        $this->assertContains($coursecontext2->id, $contextids);
+        $this->assertContainsEquals($coursecontext1->id, $contextids);
+        $this->assertContainsEquals($coursecontext2->id, $contextids);
     }
 
     /**
diff --git a/files/tests/privacy_test.php b/files/tests/privacy_test.php
index b4e7871b419..42e71467960 100644
--- a/files/tests/privacy_test.php
+++ b/files/tests/privacy_test.php
@@ -53,7 +53,7 @@ class core_files_testcase extends provider_testcase {
 
         $contextlist = provider::get_contexts_for_userid($user->id);
         $this->assertCount(1, (array) $contextlist->get_contextids());
-        $this->assertContains($userctx->id, $contextlist->get_contextids());
+        $this->assertContainsEquals($userctx->id, $contextlist->get_contextids());
     }
 
     /**
@@ -223,4 +223,4 @@ class core_files_testcase extends provider_testcase {
         // The user data in userctx2 should not be deleted.
         $this->assertCount(1, $userlist3);
     }
-}
\ No newline at end of file
+}
diff --git a/grade/grading/tests/privacy_test.php b/grade/grading/tests/privacy_test.php
index 0a84f5b613e..f0253866c14 100644
--- a/grade/grading/tests/privacy_test.php
+++ b/grade/grading/tests/privacy_test.php
@@ -72,14 +72,14 @@ class core_grading_privacy_testcase extends provider_testcase {
         // User1 has created grading definitions for instance1 and instance2.
         $contextlist = provider::get_contexts_for_userid($this->user1->id);
         $this->assertCount(2, $contextlist);
-        $this->assertContains($this->instancecontext1->id, $contextlist->get_contextids());
-        $this->assertContains($this->instancecontext2->id, $contextlist->get_contextids());
-        $this->assertNotContains($this->instancecontext0->id, $contextlist->get_contextids());
+        $this->assertContainsEquals($this->instancecontext1->id, $contextlist->get_contextids());
+        $this->assertContainsEquals($this->instancecontext2->id, $contextlist->get_contextids());
+        $this->assertNotContainsEquals($this->instancecontext0->id, $contextlist->get_contextids());
 
         // User2 has only modified grading definitions for instance2.
         $contextlist = provider::get_contexts_for_userid($this->user2->id);
         $this->assertCount(1, $contextlist);
-        $this->assertContains($this->instancecontext2->id, $contextlist->get_contextids());
+        $this->assertContainsEquals($this->instancecontext2->id, $contextlist->get_contextids());
 
         // User0 hasn't created or modified any grading definition.
         $contextlist = provider::get_contexts_for_userid($this->user0->id);
diff --git a/group/tests/privacy_provider_test.php b/group/tests/privacy_provider_test.php
index 0f0e20c494c..d5576e3aa8f 100644
--- a/group/tests/privacy_provider_test.php
+++ b/group/tests/privacy_provider_test.php
@@ -719,8 +719,8 @@ class core_group_privacy_provider_testcase extends provider_testcase {
 
         $this->assertCount(3, $contextlist);
         // One of the user context is the one related to self-conversation. Let's test group contexts.
-        $this->assertContains($coursecontext1->id, $contextids);
-        $this->assertContains($coursecontext2->id, $contextids);
+        $this->assertContainsEquals($coursecontext1->id, $contextids);
+        $this->assertContainsEquals($coursecontext2->id, $contextids);
     }
 
     /**
diff --git a/lib/tests/grouplib_test.php b/lib/tests/grouplib_test.php
index b057d5060ae..a1e3385dbbb 100644
--- a/lib/tests/grouplib_test.php
+++ b/lib/tests/grouplib_test.php
@@ -641,8 +641,8 @@ class core_grouplib_testcase extends advanced_testcase {
         $this->assertSame($group3->name, $data->groups[$group3->id]->name);
 
         // Check we have the expected number of groupings.
-        $this->assertContains($grouping1->id, array_keys($data->groupings));
-        $this->assertContains($grouping2->id, array_keys($data->groupings));
+        $this->assertArrayHasKey($grouping1->id, $data->groupings);
+        $this->assertArrayHasKey($grouping2->id, $data->groupings);
 
         // Test a grouping-id is mapped correctly.
         $this->assertEquals($grouping2->name, $data->groupings[$grouping2->id]->name);
@@ -657,10 +657,10 @@ class core_grouplib_testcase extends advanced_testcase {
         foreach ($data->mappings as $mapping) {
             if ($mapping->groupingid === $grouping1->id) {
                 $grouping1maps++;
-                $this->assertContains($mapping->groupid, array($group1->id, $group2->id));
+                $this->assertContainsEquals($mapping->groupid, array($group1->id, $group2->id));
             } else if ($mapping->groupingid === $grouping2->id) {
                 $grouping2maps++;
-                $this->assertContains($mapping->groupid, array($group3->id, $group4->id));
+                $this->assertContainsEquals($mapping->groupid, array($group3->id, $group4->id));
             } else {
                 $this->fail('Unexpected groupingid');
             }
@@ -680,35 +680,31 @@ class core_grouplib_testcase extends advanced_testcase {
 
         // Test the groups_get_all_groups which uses this functionality.
         $groups  = groups_get_all_groups($course->id);
-        $groupkeys = array_keys($groups);
         $this->assertCount(4, $groups);
-        $this->assertContains($group1->id, $groupkeys);
-        $this->assertContains($group2->id, $groupkeys);
-        $this->assertContains($group3->id, $groupkeys);
-        $this->assertContains($group4->id, $groupkeys);
+        $this->assertArrayHasKey($group1->id, $groups);
+        $this->assertArrayHasKey($group2->id, $groups);
+        $this->assertArrayHasKey($group3->id, $groups);
+        $this->assertArrayHasKey($group4->id, $groups);
 
         $groups  = groups_get_all_groups($course->id, null, $grouping1->id);
-        $groupkeys = array_keys($groups);
         $this->assertCount(2, $groups);
-        $this->assertContains($group1->id, $groupkeys);
-        $this->assertContains($group2->id, $groupkeys);
-        $this->assertNotContains($group3->id, $groupkeys);
-        $this->assertNotContains($group4->id, $groupkeys);
+        $this->assertArrayHasKey($group1->id, $groups);
+        $this->assertArrayHasKey($group2->id, $groups);
+        $this->assertArrayNotHasKey($group3->id, $groups);
+        $this->assertArrayNotHasKey($group4->id, $groups);
 
         $groups  = groups_get_all_groups($course->id, null, $grouping2->id);
-        $groupkeys = array_keys($groups);
         $this->assertCount(2, $groups);
-        $this->assertNotContains($group1->id, $groupkeys);
-        $this->assertNotContains($group2->id, $groupkeys);
-        $this->assertContains($group3->id, $groupkeys);
-        $this->assertContains($group4->id, $groupkeys);
+        $this->assertArrayNotHasKey($group1->id, $groups);
+        $this->assertArrayNotHasKey($group2->id, $groups);
+        $this->assertArrayHasKey($group3->id, $groups);
+        $this->assertArrayHasKey($group4->id, $groups);
 
         // Test this function using an alternate column for the result index
         $groups  = groups_get_all_groups($course->id, null, $grouping2->id, 'g.name, g.id');
-        $groupkeys = array_keys($groups);
         $this->assertCount(2, $groups);
-        $this->assertNotContains($group3->id, $groupkeys);
-        $this->assertContains($group3->name, $groupkeys);
+        $this->assertArrayNotHasKey($group3->id, $groups);
+        $this->assertArrayHasKey($group3->name, $groups);
         $this->assertEquals($group3->id, $groups[$group3->name]->id);
     }
 
diff --git a/message/tests/api_test.php b/message/tests/api_test.php
index 585cc2af2e4..8654efeed96 100644
--- a/message/tests/api_test.php
+++ b/message/tests/api_test.php
@@ -1545,7 +1545,7 @@ class core_message_api_testcase extends core_message_messagelib_testcase {
         $conversations = \core_message\api::get_conversations($user1->id);
         // Consider first conversations is self-conversation.
         $this->assertCount(7, $conversations);
-        $this->assertContains($gc2->id, array_column($conversations, 'id'));
+        $this->assertContainsEquals($gc2->id, array_column($conversations, 'id'));
 
         // Delete all messages from an individual conversation the user is in - it should not be returned.
         $this->assertTrue(\core_message\api::is_user_in_conversation($user1->id, $ic1->id));
@@ -1557,7 +1557,7 @@ class core_message_api_testcase extends core_message_messagelib_testcase {
         $conversations = \core_message\api::get_conversations($user1->id);
         // Consider first conversations is self-conversation.
         $this->assertCount(6, $conversations);
-        $this->assertNotContains($ic1->id, array_column($conversations, 'id'));
+        $this->assertNotContainsEquals($ic1->id, array_column($conversations, 'id'));
     }
 
     /**
@@ -5580,8 +5580,8 @@ class core_message_api_testcase extends core_message_messagelib_testcase {
         // however, we can still determine the number and ids of any recipients this way.
         $this->assertCount(1, $events);
         $userids = array_column($events, 'userid');
-        $this->assertNotContains($user1->id, $userids);
-        $this->assertContains($user2->id, $userids);
+        $this->assertNotContainsEquals($user1->id, $userids);
+        $this->assertContainsEquals($user2->id, $userids);
     }
 
     /**
@@ -5629,9 +5629,9 @@ class core_message_api_testcase extends core_message_messagelib_testcase {
         // however, we can still determine the number and ids of any recipients this way.
         $this->assertCount(2, $events);
         $userids = array_column($events, 'userid');
-        $this->assertNotContains($user1->id, $userids);
-        $this->assertContains($user3->id, $userids);
-        $this->assertContains($user4->id, $userids);
+        $this->assertNotContainsEquals($user1->id, $userids);
+        $this->assertContainsEquals($user3->id, $userids);
+        $this->assertContainsEquals($user4->id, $userids);
     }
 
     /**
diff --git a/message/tests/externallib_test.php b/message/tests/externallib_test.php
index ed73c9db7f1..b25174b9519 100644
--- a/message/tests/externallib_test.php
+++ b/message/tests/externallib_test.php
@@ -2828,14 +2828,14 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
         $members = $result['members'];
         $this->assertCount(3, $members);
         $membersid = [$members[0]['id'], $members[1]['id'], $members[2]['id']];
-        $this->assertContains($user1->id, $membersid);
-        $this->assertContains($user2->id, $membersid);
-        $this->assertContains($user3->id, $membersid);
+        $this->assertContainsEquals($user1->id, $membersid);
+        $this->assertContainsEquals($user2->id, $membersid);
+        $this->assertContainsEquals($user3->id, $membersid);
 
         $membersfullnames = [$members[0]['fullname'], $members[1]['fullname'], $members[2]['fullname']];
-        $this->assertContains(fullname($user1), $membersfullnames);
-        $this->assertContains(fullname($user2), $membersfullnames);
-        $this->assertContains(fullname($user3), $membersfullnames);
+        $this->assertContainsEquals(fullname($user1), $membersfullnames);
+        $this->assertContainsEquals(fullname($user2), $membersfullnames);
+        $this->assertContainsEquals(fullname($user3), $membersfullnames);
 
         // Confirm the messages data is correct.
         $messages = $result['messages'];
@@ -2957,9 +2957,9 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
         $members = $result['members'];
         $this->assertCount(3, $members);
         $membersid = [$members[0]['id'], $members[1]['id'], $members[2]['id']];
-        $this->assertContains($user1->id, $membersid);
-        $this->assertContains($user2->id, $membersid);
-        $this->assertContains($user3->id, $membersid);
+        $this->assertContainsEquals($user1->id, $membersid);
+        $this->assertContainsEquals($user2->id, $membersid);
+        $this->assertContainsEquals($user3->id, $membersid);
 
         // Confirm the message data is correct.
         $messages = $result['messages'];
diff --git a/message/tests/privacy_provider_test.php b/message/tests/privacy_provider_test.php
index 07e20370e94..245049f45fe 100644
--- a/message/tests/privacy_provider_test.php
+++ b/message/tests/privacy_provider_test.php
@@ -1550,8 +1550,8 @@ class core_message_privacy_provider_testcase extends \core_privacy\tests\provide
         $contextlist = new contextlist();
         provider::add_contexts_for_conversations($contextlist, $user1->id, $component, $itemtype);
         $this->assertCount(2, $contextlist);
-        $this->assertContains($coursecontext1->id, $contextlist->get_contextids());
-        $this->assertContains($coursecontext2->id, $contextlist->get_contextids());
+        $this->assertContainsEquals($coursecontext1->id, $contextlist->get_contextids());
+        $this->assertContainsEquals($coursecontext2->id, $contextlist->get_contextids());
 
         // Test for user2 (is member of the conversation and has sent a message).
         $contextlist = new contextlist();
@@ -2012,12 +2012,12 @@ class core_message_privacy_provider_testcase extends \core_privacy\tests\provide
 
         // There should be 5 messages - 3 individual - 2 group (course2).
         $this->assertEquals(5, $DB->count_records('messages'));
-        $messages = array_keys($DB->get_records('messages'));
-        $this->assertContains($im1, $messages);
-        $this->assertContains($im2, $messages);
-        $this->assertContains($im3, $messages);
-        $this->assertContains($gm4, $messages);
-        $this->assertContains($gm5, $messages);
+        $messages = $DB->get_records('messages');
+        $this->assertArrayHasKey($im1, $messages);
+        $this->assertArrayHasKey($im2, $messages);
+        $this->assertArrayHasKey($im3, $messages);
+        $this->assertArrayHasKey($gm4, $messages);
+        $this->assertArrayHasKey($gm5, $messages);
 
         // There should be 3 user actions - 2 for reading the message, 1 for deleting.
         $this->assertEquals(3, $DB->count_records('message_user_actions'));
@@ -2529,11 +2529,11 @@ class core_message_privacy_provider_testcase extends \core_privacy\tests\provide
 
         // There should be 4 messages - 3 private + 1 group sent by user2.
         $this->assertEquals(4, $DB->count_records('messages'));
-        $messages = array_keys($DB->get_records('messages'));
-        $this->assertContains($pm1, $messages);
-        $this->assertContains($pm2, $messages);
-        $this->assertContains($pm3, $messages);
-        $this->assertContains($gm3, $messages);
+        $messages = $DB->get_records('messages');
+        $this->assertArrayHasKey($pm1, $messages);
+        $this->assertArrayHasKey($pm2, $messages);
+        $this->assertArrayHasKey($pm3, $messages);
+        $this->assertArrayHasKey($gm3, $messages);
 
         // There should be 3 user actions - 2 for reading the message, one for deleting.
         $this->assertEquals(3, $DB->count_records('message_user_actions'));
@@ -2763,11 +2763,11 @@ class core_message_privacy_provider_testcase extends \core_privacy\tests\provide
 
         // There should be 4 messages - 3 private + 1 group sent by user3.
         $this->assertEquals(4, $DB->count_records('messages'));
-        $messages = array_keys($DB->get_records('messages'));
-        $this->assertContains($pm1, $messages);
-        $this->assertContains($pm2, $messages);
-        $this->assertContains($pm3, $messages);
-        $this->assertContains($gm3, $messages);
+        $messages = $DB->get_records('messages');
+        $this->assertArrayHasKey($pm1, $messages);
+        $this->assertArrayHasKey($pm2, $messages);
+        $this->assertArrayHasKey($pm3, $messages);
+        $this->assertArrayHasKey($gm3, $messages);
 
         // There should be 3 user actions - 2 for reading the message, one for deleting.
         $this->assertEquals(3, $DB->count_records('message_user_actions'));
diff --git a/mod/assign/submission/comments/tests/privacy_test.php b/mod/assign/submission/comments/tests/privacy_test.php
index 7f1acbad528..1e9c02c4ba8 100644
--- a/mod/assign/submission/comments/tests/privacy_test.php
+++ b/mod/assign/submission/comments/tests/privacy_test.php
@@ -175,10 +175,10 @@ class assignsubmission_comments_privacy_testcase extends \mod_assign\tests\mod_a
         $userids = $userlist->get_userids();
         $this->assertCount(3, $userids);
         // User 1,2 and 3 are the expected ones in the array. User 4 isn't.
-        $this->assertContains($user1->id, $userids);
-        $this->assertContains($user2->id, $userids);
-        $this->assertContains($user3->id, $userids);
-        $this->assertNotContains($user4->id, $userids);
+        $this->assertContainsEquals($user1->id, $userids);
+        $this->assertContainsEquals($user2->id, $userids);
+        $this->assertContainsEquals($user3->id, $userids);
+        $this->assertNotContainsEquals($user4->id, $userids);
     }
 
     /**
diff --git a/mod/assign/tests/locallib_test.php b/mod/assign/tests/locallib_test.php
index 7836bbcf3a2..77d260c7885 100644
--- a/mod/assign/tests/locallib_test.php
+++ b/mod/assign/tests/locallib_test.php
@@ -3388,23 +3388,23 @@ Anchor link 2:<a title=\"bananas\" href=\"../logo-240x60.gif\">Link text</a>
         // Get shared group members for students 0 and 1.
         $groupmembers = $assign->get_shared_group_members($cm, $student1->id);
         $this->assertCount(2, $groupmembers);
-        $this->assertContains($student1->id, $groupmembers);
-        $this->assertContains($student2->id, $groupmembers);
+        $this->assertContainsEquals($student1->id, $groupmembers);
+        $this->assertContainsEquals($student2->id, $groupmembers);
 
         $groupmembers = $assign->get_shared_group_members($cm, $student2->id);
         $this->assertCount(2, $groupmembers);
-        $this->assertContains($student1->id, $groupmembers);
-        $this->assertContains($student2->id, $groupmembers);
+        $this->assertContainsEquals($student1->id, $groupmembers);
+        $this->assertContainsEquals($student2->id, $groupmembers);
 
         $groupmembers = $assign->get_shared_group_members($cm, $student3->id);
         $this->assertCount(2, $groupmembers);
-        $this->assertContains($student3->id, $groupmembers);
-        $this->assertContains($student4->id, $groupmembers);
+        $this->assertContainsEquals($student3->id, $groupmembers);
+        $this->assertContainsEquals($student4->id, $groupmembers);
 
         $groupmembers = $assign->get_shared_group_members($cm, $student4->id);
         $this->assertCount(2, $groupmembers);
-        $this->assertContains($student3->id, $groupmembers);
-        $this->assertContains($student4->id, $groupmembers);
+        $this->assertContainsEquals($student3->id, $groupmembers);
+        $this->assertContainsEquals($student4->id, $groupmembers);
     }
 
     /**
@@ -3447,25 +3447,25 @@ Anchor link 2:<a title=\"bananas\" href=\"../logo-240x60.gif\">Link text</a>
         // Get shared group members for students 0 and 1.
         $groupmembers = $assign->get_shared_group_members($cm, $student1->id);
         $this->assertCount(4, $groupmembers);
-        $this->assertContains($student1->id, $groupmembers);
-        $this->assertContains($student2->id, $groupmembers);
-        $this->assertContains($student3->id, $groupmembers);
-        $this->assertContains($student4->id, $groupmembers);
+        $this->assertContainsEquals($student1->id, $groupmembers);
+        $this->assertContainsEquals($student2->id, $groupmembers);
+        $this->assertContainsEquals($student3->id, $groupmembers);
+        $this->assertContainsEquals($student4->id, $groupmembers);
 
         $groupmembers = $assign->get_shared_group_members($cm, $student2->id);
         $this->assertCount(2, $groupmembers);
-        $this->assertContains($student1->id, $groupmembers);
-        $this->assertContains($student2->id, $groupmembers);
+        $this->assertContainsEquals($student1->id, $groupmembers);
+        $this->assertContainsEquals($student2->id, $groupmembers);
 
         $groupmembers = $assign->get_shared_group_members($cm, $student3->id);
         $this->assertCount(2, $groupmembers);
-        $this->assertContains($student3->id, $groupmembers);
-        $this->assertContains($student4->id, $groupmembers);
+        $this->assertContainsEquals($student3->id, $groupmembers);
+        $this->assertContainsEquals($student4->id, $groupmembers);
 
         $groupmembers = $assign->get_shared_group_members($cm, $student4->id);
         $this->assertCount(2, $groupmembers);
-        $this->assertContains($student3->id, $groupmembers);
-        $this->assertContains($student4->id, $groupmembers);
+        $this->assertContainsEquals($student3->id, $groupmembers);
+        $this->assertContainsEquals($student4->id, $groupmembers);
     }
 
     /**
diff --git a/mod/data/tests/search_test.php b/mod/data/tests/search_test.php
index e88e58214a2..53e05cfdbbb 100644
--- a/mod/data/tests/search_test.php
+++ b/mod/data/tests/search_test.php
@@ -286,9 +286,9 @@ class mod_data_search_test extends advanced_testcase {
         $recordids = data_get_all_recordids($data1->id);
         $newrecordids = data_get_advance_search_ids($recordids, $searcharray, $data1->id);
 
-        $this->assertContains($record11, $newrecordids);
-        $this->assertContains($record12, $newrecordids);
-        $this->assertNotContains($record13, $newrecordids);
+        $this->assertContainsEquals($record11, $newrecordids);
+        $this->assertContainsEquals($record12, $newrecordids);
+        $this->assertNotContainsEquals($record13, $newrecordids);
     }
 
     /**
diff --git a/mod/h5pactivity/tests/privacy_test.php b/mod/h5pactivity/tests/privacy_test.php
index 9966abb5711..03fd928b856 100644
--- a/mod/h5pactivity/tests/privacy_test.php
+++ b/mod/h5pactivity/tests/privacy_test.php
@@ -67,7 +67,7 @@ class mod_h5pactivity_privacy_testcase extends provider_testcase {
         // The student1 has data in the mod_h5pactivity context.
         $contextlist = provider::get_contexts_for_userid($this->student1->id);
         $this->assertCount(1, (array) $contextlist->get_contextids());
-        $this->assertContains($this->context->id, $contextlist->get_contextids());
+        $this->assertContainsEquals($this->context->id, $contextlist->get_contextids());
     }
 
     /**
diff --git a/mod/quiz/accessrule/seb/tests/quiz_settings_test.php b/mod/quiz/accessrule/seb/tests/quiz_settings_test.php
index 60542b1e262..705cb5831c9 100644
--- a/mod/quiz/accessrule/seb/tests/quiz_settings_test.php
+++ b/mod/quiz/accessrule/seb/tests/quiz_settings_test.php
@@ -210,7 +210,7 @@ class quizaccess_seb_quiz_settings_testcase extends advanced_testcase {
         $quizsettings->set('allowedbrowserexamkeys', $bek);
         $quizsettings->validate();
         $errors = $quizsettings->get_errors();
-        $this->assertContains($expectederrorstring, $errors);
+        $this->assertContainsEquals($expectederrorstring, $errors);
     }
 
     /**
diff --git a/mod/quiz/accessrule/seb/tests/rule_test.php b/mod/quiz/accessrule/seb/tests/rule_test.php
index 20e2780d58f..265d443446b 100644
--- a/mod/quiz/accessrule/seb/tests/rule_test.php
+++ b/mod/quiz/accessrule/seb/tests/rule_test.php
@@ -885,7 +885,7 @@ class quizaccess_seb_rule__testcase extends advanced_testcase {
             'filemanager_sebconfigfile' => 0,
         ], [], $form);
 
-        $this->assertContains(get_string('filenotpresent', 'quizaccess_seb'), $errors);
+        $this->assertContainsEquals(get_string('filenotpresent', 'quizaccess_seb'), $errors);
     }
 
     /**
diff --git a/mod/scorm/tests/privacy_test.php b/mod/scorm/tests/privacy_test.php
index e7566713e0f..1484a81a3c7 100644
--- a/mod/scorm/tests/privacy_test.php
+++ b/mod/scorm/tests/privacy_test.php
@@ -66,7 +66,7 @@ class mod_scorm_testcase extends provider_testcase {
         // The student1 has data in the SCORM context.
         $contextlist = provider::get_contexts_for_userid($this->student1->id);
         $this->assertCount(1, (array) $contextlist->get_contextids());
-        $this->assertContains($this->context->id, $contextlist->get_contextids());
+        $this->assertContainsEquals($this->context->id, $contextlist->get_contextids());
     }
 
     /**
diff --git a/privacy/tests/contextlist_test.php b/privacy/tests/contextlist_test.php
index 13db8120a5b..b81cdd631d3 100644
--- a/privacy/tests/contextlist_test.php
+++ b/privacy/tests/contextlist_test.php
@@ -111,8 +111,8 @@ class contextlist_test extends advanced_testcase {
         $this->assertCount(2, $cl);
 
         $contexts = $cl->get_contextids();
-        $this->assertContains(\context_user::instance($user1->id)->id, $contexts);
-        $this->assertContains(\context_user::instance($user2->id)->id, $contexts);
+        $this->assertContainsEquals(\context_user::instance($user1->id)->id, $contexts);
+        $this->assertContainsEquals(\context_user::instance($user2->id)->id, $contexts);
     }
 
     /**
diff --git a/question/type/random/tests/questiontype_test.php b/question/type/random/tests/questiontype_test.php
index 38a38d29f61..444006525f5 100644
--- a/question/type/random/tests/questiontype_test.php
+++ b/question/type/random/tests/questiontype_test.php
@@ -127,6 +127,6 @@ class qtype_random_test extends advanced_testcase {
 
         $q = question_bank::load_question($randomquestion->id);
 
-        $this->assertContains($q->id, array($question1->id, $question2->id));
+        $this->assertContainsEquals($q->id, array($question1->id, $question2->id));
     }
 }