packages/test-utils: initial test registry with ErrorApi mock + tests

packages/test-utils/src/testUtils/appWrappers.test.tsx

@@ -14,11 +14,18 @@
  * limitations under the License.
  */
 
-import React, { FC } from 'react';
+import React, { FC, useEffect } from 'react';
 import { render } from '@testing-library/react';
 import { wrapInTestApp, renderInTestApp } from './appWrappers';
 import { Route } from 'react-router';
 import { withLogCollector } from '@backstage/test-utils-core';
+import {
+  useApi,
+  errorApiRef,
+  ApiProvider,
+  ApiRegistry,
+} from '@backstage/core-api';
+import { MockErrorApi } from './apis';
 
 describe('wrapInTestApp', () => {
   it('should provide routing and warn about missing act()', async () => {
@@ -69,4 +76,44 @@ describe('wrapInTestApp', () => {
     const rendered = await renderInTestApp(<Foo />);
     expect(rendered.getByText('foo')).toBeInTheDocument();
   });
+
+  it('should provide mock API implementations', async () => {
+    const A: FC<{}> = () => {
+      const errorApi = useApi(errorApiRef);
+      errorApi.post(new Error('NOPE'));
+      return null;
+    };
+
+    const { error } = await withLogCollector(['error'], async () => {
+      await expect(renderInTestApp(A)).rejects.toThrow('NOPE');
+    });
+
+    expect(error).toEqual([
+      expect.stringMatching(
+        /^Error: Uncaught \[Error: MockErrorApi received unexpected error, Error: NOPE\]/,
+      ),
+      expect.stringMatching(/^The above error occurred in the <A> component:/),
+    ]);
+  });
+
+  it('should allow custom API implementations', async () => {
+    const mockErrorApi = new MockErrorApi({ collect: true });
+
+    const A: FC<{}> = () => {
+      const errorApi = useApi(errorApiRef);
+      useEffect(() => {
+        errorApi.post(new Error('NOPE'));
+      }, [errorApi]);
+      return <p>foo</p>;
+    };
+
+    const rendered = await renderInTestApp(
+      <ApiProvider apis={ApiRegistry.with(errorApiRef, mockErrorApi)}>
+        <A />
+      </ApiProvider>,
+    );
+
+    expect(rendered.getByText('foo')).toBeInTheDocument();
+    expect(mockErrorApi.getErrors()).toEqual([{ error: new Error('NOPE') }]);
+  });
 });

packages/test-utils/src/testUtils/appWrappers.tsx

@@ -20,11 +20,11 @@ import { Route } from 'react-router-dom';
 import { lightTheme } from '@backstage/theme';
 import privateExports, {
   defaultSystemIcons,
-  ApiTestRegistry,
   BootErrorPageProps,
 } from '@backstage/core-api';
 import { RenderResult } from '@testing-library/react';
 import { renderWithEffects } from '@backstage/test-utils-core';
+import { createMockApiRegistry } from './mockApiRegistry';
 const { PrivateAppImpl } = privateExports;
 
 const NotFoundErrorPage = () => {
@@ -57,9 +57,10 @@ export function wrapInTestApp(
   options: TestAppOptions = {},
 ): ReactElement {
   const { routeEntries = ['/'] } = options;
+  const apis = createMockApiRegistry();
 
   const app = new PrivateAppImpl({
-    apis: new ApiTestRegistry(),
+    apis,
     components: {
       NotFoundErrorPage,
       BootErrorPage,

packages/test-utils/src/testUtils/mockApiRegistry.ts

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2020 Spotify AB
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { ApiTestRegistry } from '@backstage/core-api';
+import { MockErrorApi } from './apis';
+
+export function createMockApiRegistry(): ApiTestRegistry {
+  const registry = new ApiTestRegistry();
+
+  registry.register(MockErrorApi.factory);
+
+  return registry;
+}