diff --git a/lib/tests/accesslib_test.php b/lib/tests/accesslib_test.php
index 568db66b18b..42d147a5dd8 100644
--- a/lib/tests/accesslib_test.php
+++ b/lib/tests/accesslib_test.php
@@ -3567,9 +3567,12 @@ class core_accesslib_testcase extends advanced_testcase {
     protected function assert_capability_list_contains($expected, $actual) {
         $actualnames = [];
         foreach ($actual as $cap) {
-            $actualnames[$cap->name] = $cap->name;
+            $actualnames[] = $cap->name;
+        }
+        // Verify each expected element exists.
+        foreach ($expected as $key => $value) {
+            $this->assertContains($value, $actualnames);
         }
-        $this->assertArraySubset(array_combine($expected, $expected), $actualnames);
     }
 
     /**
diff --git a/mod/forum/tests/grades_gradeitems_test.php b/mod/forum/tests/grades_gradeitems_test.php
index 40df1658709..b68c84cf95f 100644
--- a/mod/forum/tests/grades_gradeitems_test.php
+++ b/mod/forum/tests/grades_gradeitems_test.php
@@ -48,8 +48,12 @@ class gradeitems_test extends advanced_testcase {
         $mappings = component_gradeitems::get_itemname_mapping_for_component('mod_forum');
         $this->assertIsArray($mappings);
         $this->assertCount(2, $mappings);
-        $this->assertArraySubset([0 => 'rating'], $mappings);
-        $this->assertArraySubset([1 => 'forum'], $mappings);
+        $expected = [0 => 'rating', 1 => 'forum'];
+        // Verify each expected element exists and its value matches.
+        foreach ($expected as $key => $value) {
+            $this->assertArrayHasKey($key, $mappings);
+            $this->assertSame($value, $mappings[$key]);
+        }
     }
 
     /**