Tests

tests/src/Kernel/ViewsIntegrationTest.php

@@ -397,4 +397,12 @@ class ViewsIntegrationTest extends EntityHierarchyKernelTestBase {
     $this->assertEquals(5, substr_count($output, ' is child of'));
   }
 
+  /**
+   * Tests target_id filter uses core's entity_reference plugin.
+   */
+  public function testEntityReferenceFilterHandler(): void {
+    $data = \Drupal::service('views.views_data')->getAll();
+    $this->assertEquals('entity_reference', $data['entity_test__parents']['parents_target_id']['filter']['id']);
+  }
+
 }