add clarifications; unify test names

Author: thymikee

src/__tests__/auto-cleanup-skip.js renamed to src/__tests__/auto-cleanup-skip.test.js

@@ -4,7 +4,7 @@ import { View } from 'react-native';
 let render;
 beforeAll(() => {
   process.env.RNTL_SKIP_AUTO_CLEANUP = 'true';
-  const rtl = require('../');
+  const rtl = require('..');
   render = rtl.render;
 });
 

src/__tests__/auto-cleanup.js renamed to src/__tests__/auto-cleanup.test.js

@@ -20,6 +20,10 @@ class Test extends React.Component<*> {
   }
 }
 
+afterEach(() => {
+  jest.useRealTimers();
+});
+
 // This just verifies that by importing RNTL in an environment which supports afterEach (like jest)
 // we'll get automatic cleanup between tests.
 test('component is mounted, but not umounted before test ends', () => {

src/flushMicroTasks.js

@@ -1,25 +1,22 @@
 // @flow
-
 import { printDeprecationWarning } from './helpers/errors';
 
-type Thenable = { then: (() => mixed) => mixed };
+type Thenable<T> = { then: (() => T) => mixed };
 
 /**
  * Wait for microtasks queue to flush
  */
-export default function flushMicrotasksQueue(): Thenable {
+export default function flushMicrotasksQueue<T>(): Thenable<T> {
   printDeprecationWarning('flushMicrotasksQueue');
   return flushMicroTasks();
 }
 
-// let's try to get node's version of setImmediate, bypassing fake timers if
-// any. $FlowFixMe - timers is internal Node module
-const enqueueTask = require('timers').setImmediate;
-
-export function flushMicroTasks(): Thenable {
+export function flushMicroTasks<T>(): Thenable<T> {
   return {
+    // using "thenable" instead of a Promise, because otherwise it breaks when
+    // using "modern" fake timers
     then(resolve) {
-      enqueueTask(resolve);
+      setImmediate(resolve);
     },
   };
 }