use enum-like object for timer modes

Author: mikeduminy

src/__tests__/timerUtils.js

@@ -1,19 +1,19 @@
 import { setTimeout } from '../helpers/getTimerFuncs';
 
-const FakeTimerTypes = [
-  'default',
-  'legacy',
-  // 'modern', // broken for now
-];
+const TimerMode = {
+  Default: 'default',
+  Legacy: 'legacy',
+  Modern: 'modern', // broken for now
+};
 
 function setupFakeTimers(fakeTimerType) {
   switch (fakeTimerType) {
-    case 'legacy':
-    case 'modern': {
+    case TimerMode.Legacy:
+    case TimerMode.Modern: {
       jest.useFakeTimers(fakeTimerType);
       break;
     }
-    case 'default':
+    case TimerMode.Default:
     default: {
       jest.useFakeTimers();
     }
@@ -24,4 +24,4 @@ async function sleep(ms) {
   return new Promise((resolve) => setTimeout(resolve, ms));
 }
 
-export { FakeTimerTypes, setupFakeTimers, sleep };
+export { TimerMode, setupFakeTimers, sleep };

src/__tests__/waitFor.test.js

@@ -2,7 +2,7 @@
 import * as React from 'react';
 import { Text, TouchableOpacity, View } from 'react-native';
 import { fireEvent, render, waitFor } from '..';
-import { FakeTimerTypes, setupFakeTimers, sleep } from './timerUtils';
+import { TimerMode, setupFakeTimers, sleep } from './timerUtils';
 
 class Banana extends React.Component<any> {
   changeFresh = () => {
@@ -80,7 +80,7 @@ test('waits for element with custom interval', async () => {
   expect(mockFn).toHaveBeenCalledTimes(3);
 });
 
-test.each(FakeTimerTypes)(
+test.each([TimerMode.Default, TimerMode.Legacy])(
   'waits for element until it stops throwing using %s fake timers',
   async (fakeTimerType) => {
     setupFakeTimers(fakeTimerType);
@@ -96,7 +96,7 @@ test.each(FakeTimerTypes)(
   }
 );
 
-test.each(FakeTimerTypes)(
+test.each([TimerMode.Default, TimerMode.Legacy])(
   'waits for assertion until timeout is met with %s fake timers',
   async (fakeTimerType) => {
     setupFakeTimers(fakeTimerType);
@@ -115,7 +115,7 @@ test.each(FakeTimerTypes)(
   }
 );
 
-test.each(FakeTimerTypes)(
+test.each([TimerMode.Default, TimerMode.Legacy])(
   'awaiting something that succeeds before timeout works with %s fake timers',
   async (fakeTimerType) => {
     setupFakeTimers(fakeTimerType);
@@ -142,7 +142,7 @@ test.each(FakeTimerTypes)(
 // it is included to show that the previous approach of faking modern timers still works
 // the gotcha is that the try catch will fail to catch the final error, which is why we need to stop throwing
 test('non-awaited approach is not affected by fake modern timers', async () => {
-  jest.useFakeTimers('modern');
+  setupFakeTimers(TimerMode.Modern);
 
   let calls = 0;
   const mockFn = jest.fn(() => {