Failing identifier polymorphic scenario

packages/-ember-data/tests/integration/identifiers/polymorphic-scenarios-test.ts

@@ -0,0 +1,115 @@
+import { module, test } from 'qunit';
+import { setupTest } from 'ember-qunit';
+import { IDENTIFIERS } from '@ember-data/canary-features';
+import Store from '@ember-data/store';
+import Model, { attr, belongsTo } from '@ember-data/model';
+import Adapter from '@ember-data/adapter';
+import Serializer from '@ember-data/serializer';
+import { resolve } from 'rsvp';
+
+if (IDENTIFIERS) {
+  module('Integration | Identifiers - polymorphic scenarios', function(hooks) {
+    setupTest(hooks);
+
+    module('single-table', function(hooks) {
+      let store;
+      let calls;
+      class TestSerializer extends Serializer {
+        normalizeResponse(_, __, payload) {
+          return payload;
+        }
+      }
+      class TestAdapter extends Adapter {
+        shouldBackgroundReloadRecord() {
+          return false;
+        }
+      }
+
+      class CarAdapter extends TestAdapter {
+        findRecord() {
+          return resolve({
+            data: {
+              id: '1',
+              type: 'ferrari',
+              attributes: {
+                color: 'red'
+              },
+            },
+          });
+        }
+      }
+
+      class FerrariAdapter extends TestAdapter {
+        findRecord() {
+          return resolve({
+            data: {
+              id: '1',
+              type: 'ferrari',
+              attributes: {
+                color: 'red'
+              },
+            },
+          });
+        }
+      }
+
+      class DealershipAdapter extends TestAdapter {
+        findRecord() {
+          return resolve({
+            data: {
+              id: '1',
+              type: 'dealership',
+              attributes: {
+                name: 'Brand new* car'
+              },
+              relationships: {
+                car: {
+                  data: { id: 1, type: 'ferrari' },
+                },
+              },
+            }
+          });
+        }
+      }
+
+      hooks.beforeEach(function() {
+        const { owner } = this;
+
+        class Car extends Model {
+          @attr() color: string;
+        }
+
+        class Ferrari extends Car {
+          @attr() color: string;
+        }
+
+        class Dealership extends Model {
+          @attr() name: string;
+          @belongsTo("car", { polymorphic: true }) car;
+        }
+
+        owner.register('adapter:car', CarAdapter);
+        owner.register('adapter:ferrari', FerrariAdapter);
+        owner.register('adapter:dealership', DealershipAdapter);
+        owner.register('serializer:application', TestSerializer);
+        owner.register('model:car', Car);
+        owner.register('model:ferrari', Ferrari);
+        owner.register('model:dealership', Dealership);
+        owner.register('service:store', Store);
+
+        store = owner.lookup('service:store');
+
+      });
+
+      test(`Identity of polymorphic relations can change type`, async function(assert) {
+        const topRecord = await store.findRecord('dealership', '1');
+        const relation = await topRecord.get('car');
+
+        assert.strictEqual(relation.id, '1');
+
+        const foundRecord = await store.findRecord('car', '1');
+        assert.strictEqual(foundRecord.id, '1');
+      });
+    });
+  });
+}