Clean up Scheduler forks (#20915)

* Clean up Scheduler forks

* Un-shadow variables

* Use timer globals directly, add a test for overrides

* Remove more window references

* Don't crash for undefined globals + tests

* Update lint config globals

* Fix test by using async act

* Add test fixture

* Delete test fixture

Author: rickhanlonii

.codesandbox/ci.json

@@ -1,6 +1,6 @@
 {
   "packages": ["packages/react", "packages/react-dom", "packages/scheduler"],
-  "buildCommand": "build --type=NODE react/index,react-dom/index,react-dom/server,react-dom/test-utils,scheduler/index,scheduler/unstable_no_dom,react/jsx-runtime,react/jsx-dev-runtime",
+  "buildCommand": "build --type=NODE react/index,react-dom/index,react-dom/server,react-dom/test-utils,scheduler/index,react/jsx-runtime,react/jsx-dev-runtime",
   "node": "12",
   "publishDirectory": {
     "react": "build/node_modules/react",

fixtures/dom/src/__tests__/wrong-act-test.js

@@ -81,12 +81,12 @@ it("doesn't warn when you use the right act + renderer: test", () => {
   });
 });
 
-it('resets correctly across renderers', () => {
+it('resets correctly across renderers', async () => {
   function Effecty() {
     React.useEffect(() => {}, []);
     return null;
   }
-  TestUtils.act(() => {
+  await TestUtils.act(async () => {
     TestRenderer.act(() => {});
     expect(() => {
       TestRenderer.create(<Effecty />);

packages/react-dom/src/__tests__/ReactTestUtilsActUnmockedScheduler-test.js

@@ -33,9 +33,7 @@ function unmount(dom) {
 
 beforeEach(() => {
   jest.resetModules();
-  jest.mock('scheduler', () =>
-    require.requireActual('scheduler/unstable_no_dom'),
-  );
+  jest.unmock('scheduler');
   yields = [];
   React = require('react');
   ReactDOM = require('react-dom');

packages/react-dom/src/__tests__/ReactUnmockedSchedulerWarning-test.internal.js

@@ -17,7 +17,7 @@ function App() {
 
 beforeEach(() => {
   jest.resetModules();
-  jest.mock('scheduler', () => require('scheduler/unstable_no_dom'));
+  jest.unmock('scheduler');
   React = require('react');
   ReactDOM = require('react-dom');
   ReactFeatureFlags = require('shared/ReactFeatureFlags');

packages/react-dom/src/__tests__/ReactUnmockedSchedulerWarning-test.js

@@ -16,9 +16,7 @@ function App() {
 
 beforeEach(() => {
   jest.resetModules();
-  jest.mock('scheduler', () =>
-    require.requireActual('scheduler/unstable_no_dom'),
-  );
+  jest.unmock('scheduler');
   React = require('react');
   ReactDOM = require('react-dom');
 });

packages/scheduler/index.js

@@ -7,4 +7,4 @@
 
 'use strict';
 
-export * from './src/forks/SchedulerDOM';
+export * from './src/forks/Scheduler';

packages/scheduler/npm/index.js

@@ -1,8 +1,6 @@
 'use strict';
 
-if (typeof window === 'undefined' || typeof MessageChannel !== 'function') {
-  module.exports = require('./unstable_no_dom');
-} else if (process.env.NODE_ENV === 'production') {
+if (process.env.NODE_ENV === 'production') {
   module.exports = require('./cjs/scheduler.production.min.js');
 } else {
   module.exports = require('./cjs/scheduler.development.js');

packages/scheduler/npm/unstable_no_dom.js

@@ -26,7 +26,6 @@
     "build-info.json",
     "index.js",
     "unstable_mock.js",
-    "unstable_no_dom.js",
     "unstable_post_task.js",
     "cjs/",
     "umd/"

packages/scheduler/package.json

@@ -32,11 +32,9 @@ let NormalPriority;
 describe('SchedulerBrowser', () => {
   beforeEach(() => {
     jest.resetModules();
-
-    // Un-mock scheduler
-    jest.mock('scheduler', () => require.requireActual('scheduler'));
-
     runtime = installMockBrowserRuntime();
+    jest.unmock('scheduler');
+
     performance = global.performance;
     Scheduler = require('scheduler');
     cancelCallback = Scheduler.unstable_cancelCallback;
@@ -68,21 +66,16 @@ describe('SchedulerBrowser', () => {
       },
     };
 
-    const window = {};
-    global.window = window;
-
-    // TODO: Scheduler no longer requires these methods to be polyfilled. But
-    // maybe we want to continue warning if they don't exist, to preserve the
-    // option to rely on it in the future?
-    window.requestAnimationFrame = window.cancelAnimationFrame = () => {};
+    // Delete node provide setImmediate so we fall through to MessageChannel.
+    delete global.setImmediate;
 
-    window.setTimeout = (cb, delay) => {
+    global.setTimeout = (cb, delay) => {
       const id = timerIDCounter++;
       log(`Set Timer`);
       // TODO
       return id;
     };
-    window.clearTimeout = id => {
+    global.clearTimeout = id => {
       // TODO
     };