Update jest to v26

package.json

@@ -68,10 +68,9 @@
     "google-closure-compiler": "^20200517.0.0",
     "gzip-size": "^5.1.1",
     "jasmine-check": "^1.0.0-rc.0",
-    "jest": "^25.2.7",
-    "jest-cli": "^25.2.7",
-    "jest-diff": "^25.2.6",
-    "jest-environment-jsdom-sixteen": "^1.0.3",
+    "jest": "^26.6.3",
+    "jest-cli": "^26.6.3",
+    "jest-diff": "^26.6.2",
     "jest-snapshot-serializer-raw": "^1.1.0",
     "minimatch": "^3.0.4",
     "minimist": "^1.2.3",

packages/react-reconciler/src/__tests__/ReactSchedulerIntegration-test.js

@@ -187,7 +187,7 @@ describe(
       jest.resetModules();
 
       jest.mock('scheduler', () => {
-        const actual = require.requireActual('scheduler/unstable_mock');
+        const actual = jest.requireActual('scheduler/unstable_mock');
         return {
           ...actual,
           unstable_shouldYield() {
@@ -207,7 +207,7 @@ describe(
 
     afterEach(() => {
       jest.mock('scheduler', () =>
-        require.requireActual('scheduler/unstable_mock'),
+        jest.requireActual('scheduler/unstable_mock'),
       );
     });
 

packages/react/src/__tests__/ReactProfiler-test.internal.js

@@ -229,7 +229,7 @@ describe(`onRender`, () => {
     // Mock the Scheduler module so we can track how many times the current
     // time is read
     jest.mock('scheduler', obj => {
-      const ActualScheduler = require.requireActual('scheduler/unstable_mock');
+      const ActualScheduler = jest.requireActual('scheduler/unstable_mock');
       return {
         ...ActualScheduler,
         unstable_now: function mockUnstableNow() {
@@ -267,9 +267,7 @@ describe(`onRender`, () => {
     ]);
 
     // Restore original mock
-    jest.mock('scheduler', () =>
-      require.requireActual('scheduler/unstable_mock'),
-    );
+    jest.mock('scheduler', () => jest.requireActual('scheduler/unstable_mock'));
   });
 
   it('does not report work done on a sibling', () => {

packages/scheduler/src/__tests__/SchedulerPostTask-test.js

@@ -31,7 +31,7 @@ describe('SchedulerPostTask', () => {
   beforeEach(() => {
     jest.resetModules();
     jest.mock('scheduler', () =>
-      require.requireActual('scheduler/unstable_post_task'),
+      jest.requireActual('scheduler/unstable_post_task'),
     );
 
     runtime = installMockBrowserRuntime();

scripts/jest/config.base.js

@@ -25,6 +25,5 @@ module.exports = {
 
   testSequencer: require.resolve('./jestSequencer'),
 
-  // TODO: Upgrade to Jest 26 which uses jsdom 16 by default.
-  testEnvironment: require.resolve('jest-environment-jsdom-sixteen'),
+  testEnvironment: 'jsdom',
 };

scripts/jest/setupHostConfigs.js

@@ -3,7 +3,7 @@
 const inlinedHostConfigs = require('../shared/inlinedHostConfigs');
 
 jest.mock('react-reconciler/src/ReactFiberReconciler', () => {
-  return require.requireActual(
+  return jest.requireActual(
     __VARIANT__
       ? 'react-reconciler/src/ReactFiberReconciler.new'
       : 'react-reconciler/src/ReactFiberReconciler.old'
@@ -16,7 +16,7 @@ const shimHostConfigPath = 'react-reconciler/src/ReactFiberHostConfig';
 jest.mock('react-reconciler', () => {
   return config => {
     jest.mock(shimHostConfigPath, () => config);
-    return require.requireActual('react-reconciler');
+    return jest.requireActual('react-reconciler');
   };
 });
 const shimServerStreamConfigPath = 'react-server/src/ReactServerStreamConfig';
@@ -26,7 +26,7 @@ jest.mock('react-server', () => {
   return config => {
     jest.mock(shimServerStreamConfigPath, () => config);
     jest.mock(shimServerFormatConfigPath, () => config);
-    return require.requireActual('react-server');
+    return jest.requireActual('react-server');
   };
 });
 jest.mock('react-server/flight', () => {
@@ -39,19 +39,19 @@ jest.mock('react-server/flight', () => {
       resolveModuleMetaData: config.resolveModuleMetaData,
     }));
     jest.mock(shimFlightServerConfigPath, () =>
-      require.requireActual(
+      jest.requireActual(
         'react-server/src/forks/ReactFlightServerConfig.custom'
       )
     );
-    return require.requireActual('react-server/flight');
+    return jest.requireActual('react-server/flight');
   };
 });
 const shimFlightClientHostConfigPath =
   'react-client/src/ReactFlightClientHostConfig';
 jest.mock('react-client/flight', () => {
   return config => {
     jest.mock(shimFlightClientHostConfigPath, () => config);
-    return require.requireActual('react-client/flight');
+    return jest.requireActual('react-client/flight');
   };
 });
 
@@ -69,7 +69,7 @@ function mockAllConfigs(rendererInfo) {
     jest.mock(path, () => {
       let idx = path.lastIndexOf('/');
       let forkPath = path.substr(0, idx) + '/forks' + path.substr(idx);
-      return require.requireActual(`${forkPath}.${rendererInfo.shortName}.js`);
+      return jest.requireActual(`${forkPath}.${rendererInfo.shortName}.js`);
     });
   });
 }
@@ -85,15 +85,15 @@ inlinedHostConfigs.forEach(rendererInfo => {
   rendererInfo.entryPoints.forEach(entryPoint => {
     jest.mock(entryPoint, () => {
       mockAllConfigs(rendererInfo);
-      return require.requireActual(entryPoint);
+      return jest.requireActual(entryPoint);
     });
   });
 });
 
 // Make it possible to import this module inside
 // the React package itself.
 jest.mock('shared/ReactSharedInternals', () =>
-  require.requireActual('react/src/ReactSharedInternals')
+  jest.requireActual('react/src/ReactSharedInternals')
 );
 
-jest.mock('scheduler', () => require.requireActual('scheduler/unstable_mock'));
+jest.mock('scheduler', () => jest.requireActual('scheduler/unstable_mock'));

scripts/jest/setupTests.build.js

@@ -1,3 +1,3 @@
 'use strict';
 
-jest.mock('scheduler', () => require.requireActual('scheduler/unstable_mock'));
+jest.mock('scheduler', () => jest.requireActual('scheduler/unstable_mock'));

scripts/jest/setupTests.persistent.js

@@ -1,7 +1,7 @@
 'use strict';
 
 jest.mock('react-noop-renderer', () =>
-  require.requireActual('react-noop-renderer/persistent')
+  jest.requireActual('react-noop-renderer/persistent')
 );
 
 global.__PERSISTENT__ = true;