refactor: pass useFakeTimer config in tests

Author: mdjastrzebski

src/__tests__/auto-cleanup.test.tsx

@@ -38,13 +38,13 @@ test('component is automatically umounted after first test ends', () => {
 });
 
 test('does not time out with legacy fake timers', () => {
-  jest.useFakeTimers('legacy');
+  jest.useFakeTimers({ legacyFakeTimers: true });
   render(<Test />);
   expect(isMounted).toEqual(true);
 });
 
 test('does not time out with fake timers', () => {
-  jest.useFakeTimers('modern');
+  jest.useFakeTimers();
   render(<Test />);
   expect(isMounted).toEqual(true);
 });

src/__tests__/timers.test.ts

@@ -1,11 +1,10 @@
 import waitFor from '../waitFor';
-import { TimerMode } from './timerUtils';
 
-describe.each([TimerMode.Legacy, TimerMode.Modern])(
-  '%s fake timers tests',
-  (fakeTimerType) => {
+describe.each([false, true])(
+  'fake timers tests (legacyFakeTimers = %s)',
+  (legacyFakeTimers) => {
     beforeEach(() => {
-      jest.useFakeTimers(fakeTimerType);
+      jest.useFakeTimers({ legacyFakeTimers });
     });
 
     test('it successfully runs tests', () => {

src/__tests__/waitFor.test.tsx

@@ -79,36 +79,26 @@ test('waits for element with custom interval', async () => {
   expect(mockFn).toHaveBeenCalledTimes(2);
 });
 
-test('waits for element until it stops throwing using modern fake timers', async () => {
-  jest.useFakeTimers('modern');
-  const { getByText, queryByText } = render(<BananaContainer />);
-
-  fireEvent.press(getByText('Change freshness!'));
-  expect(queryByText('Fresh')).toBeNull();
-
-  jest.advanceTimersByTime(300);
-  const freshBananaText = await waitFor(() => getByText('Fresh'));
-
-  expect(freshBananaText.props.children).toBe('Fresh');
-});
+test.each([false, true])(
+  'waits for element until it stops throwing using fake timers (legacyFakeTimers = %s)',
+  async (legacyFakeTimers) => {
+    jest.useFakeTimers({ legacyFakeTimers });
+    const { getByText, queryByText } = render(<BananaContainer />);
 
-test('waits for element until it stops throwing using legacy fake timers', async () => {
-  jest.useFakeTimers('legacy');
-  const { getByText, queryByText } = render(<BananaContainer />);
+    fireEvent.press(getByText('Change freshness!'));
+    expect(queryByText('Fresh')).toBeNull();
 
-  fireEvent.press(getByText('Change freshness!'));
-  expect(queryByText('Fresh')).toBeNull();
-
-  jest.advanceTimersByTime(300);
-  const freshBananaText = await waitFor(() => getByText('Fresh'));
+    jest.advanceTimersByTime(300);
+    const freshBananaText = await waitFor(() => getByText('Fresh'));
 
-  expect(freshBananaText.props.children).toBe('Fresh');
-});
+    expect(freshBananaText.props.children).toBe('Fresh');
+  }
+);
 
-test.each([TimerMode.Legacy, TimerMode.Modern])(
-  'waits for assertion until timeout is met with %s fake timers',
-  async (fakeTimerType) => {
-    jest.useFakeTimers(fakeTimerType);
+test.each([false, true])(
+  'waits for assertion until timeout is met with fake timers (legacyFakeTimers = %s)',
+  async (legacyFakeTimers) => {
+    jest.useFakeTimers({ legacyFakeTimers });
 
     const mockFn = jest.fn(() => {
       throw Error('test');
@@ -124,10 +114,10 @@ test.each([TimerMode.Legacy, TimerMode.Modern])(
   }
 );
 
-test.each([TimerMode.Legacy, TimerMode.Modern])(
-  'waits for assertion until timeout is met with %s fake timers',
-  async (fakeTimerType) => {
-    jest.useFakeTimers(fakeTimerType);
+test.each([false, true])(
+  'waits for assertion until timeout is met with fake timers (legacyFakeTimers = %s)',
+  async (legacyFakeTimers) => {
+    jest.useFakeTimers({ legacyFakeTimers });
 
     const mockErrorFn = jest.fn(() => {
       throw Error('test');
@@ -150,10 +140,10 @@ test.each([TimerMode.Legacy, TimerMode.Modern])(
   }
 );
 
-test.each([TimerMode.Legacy, TimerMode.Legacy])(
-  'awaiting something that succeeds before timeout works with %s fake timers',
-  async (fakeTimerType) => {
-    jest.useFakeTimers(fakeTimerType);
+test.each([false, true])(
+  'awaiting something that succeeds before timeout works with fake timers (legacyFakeTimers = %s)',
+  async (legacyFakeTimers) => {
+    jest.useFakeTimers({ legacyFakeTimers });
 
     let calls = 0;
     const mockFn = jest.fn(() => {

src/__tests__/waitForElementToBeRemoved.test.tsx

@@ -130,10 +130,10 @@ test('waits with custom interval', async () => {
   expect(mockFn).toHaveBeenCalledTimes(4);
 });
 
-test.each([TimerMode.Legacy, TimerMode.Modern])(
-  'works with %s fake timers',
-  async (fakeTimerType) => {
-    jest.useFakeTimers(fakeTimerType);
+test.each([false, true])(
+  'works with fake timers (legacyFakeTimers = %s)',
+  async (legacyFakeTimers) => {
+    jest.useFakeTimers({ legacyFakeTimers });
 
     const mockFn = jest.fn(() => <View />);