Made some incremental progress on Jest tests

package.json

@@ -47,10 +47,10 @@
     "error-stack-parser": "^2.0.2",
     "eslint": "^6.1.0",
     "eslint-config-fbjs": "^1.1.1",
+    "eslint-plugin-babel": "^5.3.0",
     "eslint-plugin-flowtype": "^2.25.0",
     "eslint-plugin-jest": "^22.15.0",
     "eslint-plugin-no-for-of-loops": "^1.0.0",
-    "eslint-plugin-babel": "^5.3.0",
     "eslint-plugin-react": "^6.7.1",
     "eslint-plugin-react-internal": "link:./scripts/eslint-rules",
     "fbjs-scripts": "^0.8.3",
@@ -61,8 +61,8 @@
     "google-closure-compiler": "20190301.0.0",
     "gzip-size": "^3.0.0",
     "jasmine-check": "^1.0.0-rc.0",
-    "jest": "^23.1.0",
-    "jest-diff": "^23.0.1",
+    "jest": "^23",
+    "jest-diff": "^23",
     "jest-snapshot-serializer-raw": "^1.1.0",
     "minimatch": "^3.0.4",
     "minimist": "^1.2.0",
@@ -102,6 +102,7 @@
     "postinstall": "node node_modules/fbjs-scripts/node/check-dev-engines.js package.json && node ./scripts/flow/createFlowConfigs.js",
     "debug-test": "cross-env NODE_ENV=development node --inspect-brk node_modules/.bin/jest --config ./scripts/jest/config.source.js --runInBand",
     "test": "cross-env NODE_ENV=development jest --config ./scripts/jest/config.source.js",
+    "test-devtools": "cross-env NODE_ENV=development jest --config ./scripts/jest/config.devtools.js",
     "test-persistent": "cross-env NODE_ENV=development jest --config ./scripts/jest/config.source-persistent.js",
     "debug-test-persistent": "cross-env NODE_ENV=development node --inspect-brk node_modules/.bin/jest --config ./scripts/jest/config.source-persistent.js --runInBand",
     "test-prod": "cross-env NODE_ENV=production jest --config ./scripts/jest/config.source.js",

packages/react-devtools-shared/package.json

@@ -8,6 +8,7 @@
     "@reach/tooltip": "^0.2.2",
     "clipboard-js": "^0.3.6",
     "events": "^3.0.0",
+    "local-storage-fallback": "^4.1.1",
     "lodash.throttle": "^4.1.1",
     "memoize-one": "^3.1.1",
     "react-virtualized-auto-sizer": "^1.0.2"

packages/react-devtools-shared/src/__tests__/bridge-test.js

@@ -30,7 +30,7 @@ describe('Bridge', () => {
     expect(wall.send).toHaveBeenCalledWith('shutdown');
 
     // Verify that the Bridge doesn't send messages after shutdown.
-    spyOn(console, 'warn');
+    spyOnDevAndProd(console, 'warn');
     wall.send.mockClear();
     bridge.send('should not send');
     jest.runAllTimers();

packages/react-devtools-shared/src/__tests__/console-test.js

@@ -13,23 +13,10 @@ describe('console', () => {
   let unpatchConsole;
 
   beforeEach(() => {
-    const Console = require('../backend/console');
+    const Console = require('react-devtools-shared/src/backend/console');
     patchConsole = Console.patch;
     unpatchConsole = Console.unpatch;
 
-    const inject = global.__REACT_DEVTOOLS_GLOBAL_HOOK__.inject;
-    global.__REACT_DEVTOOLS_GLOBAL_HOOK__.inject = internals => {
-      inject(internals);
-
-      Console.registerRenderer(internals);
-    };
-
-    React = require('react');
-    ReactDOM = require('react-dom');
-
-    const utils = require('./utils');
-    act = utils.act;
-
     // Patch a fake console so we can verify with tests below.
     // Patching the real console is too complicated,
     // because Jest itself has hooks into it as does our test env setup.
@@ -46,7 +33,22 @@ describe('console', () => {
 
     Console.dangerous_setTargetConsoleForTesting(fakeConsole);
 
+    // Note the Console module only patches once,
+    // so it's important to patch the test console before injection.
     patchConsole();
+
+    const inject = global.__REACT_DEVTOOLS_GLOBAL_HOOK__.inject;
+    global.__REACT_DEVTOOLS_GLOBAL_HOOK__.inject = internals => {
+      inject(internals);
+
+      Console.registerRenderer(internals);
+    };
+
+    React = require('react');
+    ReactDOM = require('react-dom');
+
+    const utils = require('./utils');
+    act = utils.act;
   });
 
   function normalizeCodeLocInfo(str) {

packages/react-devtools-shared/src/__tests__/setupEnv.js

@@ -1,15 +1,19 @@
-// @flow
+'use strict';
 
-import storage from 'local-storage-fallback';
+// Import test renderer and then reset modules for two reasons:
+// 1. We don't want test renderer connected to the DevTools hooks.
+// 2. This enables us to work around the on-renderer limitation.
+// TODO This (or the resetModules below) might be the cause of the hooks erorr in some tests
+const ReactTestRenderer = require.requireActual('react-test-renderer');
 
-// In case async/await syntax is used in a test.
-import 'regenerator-runtime/runtime';
+jest.resetModules();
+
+jest.mock('react-test-renderer', () => ReactTestRenderer);
 
 // DevTools stores preferences between sessions in localStorage
 if (!global.hasOwnProperty('localStorage')) {
-  global.localStorage = storage;
+  global.localStorage = require('local-storage-fallback').default;
 }
 
 // Mimic the global we set with Webpack's DefinePlugin
 global.__DEV__ = process.env.NODE_ENV !== 'production';
-global.__TEST__ = process.env.NODE_ENV === 'test';

packages/react-devtools-shared/src/__tests__/utils.js

@@ -40,7 +40,8 @@ export async function actAsync(
   });
 
   if (recursivelyFlush) {
-    while (jest.getTimerCount() > 0) {
+    // TODO (Jest v24)  Replace with jest.getTimerCount() after we upgrade Jest
+    while (global.mockGetTimersCount() > 0) {
       // $FlowFixMe Flow doens't know about "await act()" yet
       await actDOM(async () => {
         await actTestRenderer(async () => {

scripts/jest/config.devtools.js

@@ -0,0 +1,27 @@
+'use strict';
+
+const baseConfig = require('./config.base');
+
+module.exports = Object.assign({}, baseConfig, {
+  testRegex: 'packages/react-devtools-shared/src/__tests__/[^]+.test.js$',
+  modulePathIgnorePatterns: [],
+  snapshotSerializers: [
+    require.resolve(
+      '../../packages/react-devtools-shared/src/__tests__/inspectedElementSerializer.js'
+    ),
+    require.resolve(
+      '../../packages/react-devtools-shared/src/__tests__/storeSerializer.js'
+    ),
+  ],
+  setupFiles: [
+    ...baseConfig.setupFiles,
+    require.resolve('./setupHostConfigs.js'),
+    require.resolve(
+      '../../packages/react-devtools-shared/src/__tests__/setupEnv.js'
+    ),
+  ],
+  // TODO (Jest v24) Rename "setupFilesAfterEnv" after Jest upgrade
+  setupTestFrameworkScriptFile: require.resolve(
+    '../../packages/react-devtools-shared/src/__tests__/setupTests.js'
+  ),
+});

scripts/jest/preprocessor.js

@@ -43,7 +43,10 @@ const babelOptions = {
 
     // This optimization is important for extremely performance-sensitive (e.g. React source).
     // It's okay to disable it for tests.
-    [require.resolve('@babel/plugin-transform-block-scoping'), {throwIfClosureRequired: false}],
+    [
+      require.resolve('@babel/plugin-transform-block-scoping'),
+      {throwIfClosureRequired: false},
+    ],
   ],
   retainLines: true,
 };

yarn.lock

@@ -1879,6 +1879,7 @@ array.prototype.find@^2.0.1:
 arrify@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/arrify/-/arrify-1.0.1.tgz#898508da2226f380df904728456849c1501a4b0d"
+  integrity sha1-iYUI2iIm84DfkEcoRWhJwVAaSw0=
 
 arrify@^2.0.1:
   version "2.0.1"
@@ -3513,6 +3514,11 @@ cookie@0.4.0:
   resolved "https://registry.yarnpkg.com/cookie/-/cookie-0.4.0.tgz#beb437e7022b3b6d49019d088665303ebe9c14ba"
   integrity sha512-+Hp8fLp57wnUSt0tY0tHEXh4voZRDnoIrZPqlo3DPiI4y9lwg/jqx+1Om94/W6ZaPDOUbnjOt/99w66zk+l1Xg==
 
+cookie@^0.3.1:
+  version "0.3.1"
+  resolved "https://registry.yarnpkg.com/cookie/-/cookie-0.3.1.tgz#e7e0a1f9ef43b4c8ba925c5c5a96e806d16873bb"
+  integrity sha1-5+Ch+e9DtMi6klxcWpboBtFoc7s=
+
 copy-concurrently@^1.0.0:
   version "1.0.5"
   resolved "https://registry.yarnpkg.com/copy-concurrently/-/copy-concurrently-1.0.5.tgz#92297398cae34937fcafd6ec8139c18051f0b5e0"
@@ -7215,7 +7221,7 @@ jest-config@^23.6.0:
     micromatch "^2.3.11"
     pretty-format "^23.6.0"
 
-jest-diff@^23.0.1, jest-diff@^23.6.0:
+jest-diff@^23, jest-diff@^23.6.0:
   version "23.6.0"
   resolved "https://registry.yarnpkg.com/jest-diff/-/jest-diff-23.6.0.tgz#1500f3f16e850bb3d71233408089be099f610c7d"
   integrity sha512-Gz9l5Ov+X3aL5L37IT+8hoCUsof1CVYBb2QEkOupK64XyRR3h+uRpYIm97K7sY8diFxowR8pIGEdyfMKTixo3g==
@@ -7536,7 +7542,7 @@ jest-worker@^24.6.0:
     merge-stream "^1.0.1"
     supports-color "^6.1.0"
 
-jest@^23.1.0:
+jest@^23:
   version "23.6.0"
   resolved "https://registry.yarnpkg.com/jest/-/jest-23.6.0.tgz#ad5835e923ebf6e19e7a1d7529a432edfee7813d"
   integrity sha512-lWzcd+HSiqeuxyhG+EnZds6iO3Y3ZEnMrfZq/OTGvF/C+Z4fPMCdhWTGSAiO2Oym9rbEXfwddHhh6jqrTF3+Lw==
@@ -7941,6 +7947,13 @@ loader-utils@1.2.3, loader-utils@^1.0.2, loader-utils@^1.1.0, loader-utils@^1.2.
     emojis-list "^2.0.0"
     json5 "^1.0.1"
 
+local-storage-fallback@^4.1.1:
+  version "4.1.1"
+  resolved "https://registry.yarnpkg.com/local-storage-fallback/-/local-storage-fallback-4.1.1.tgz#6dc964635c8e9ab6d522d7d88538f465b62bd161"
+  integrity sha512-Ka4rem1FOgvIaPMokxXTP8DgW8gjfAQSdJC8TGrplDug7vh3b0PZnY/9euG3O3cIGAvJLp33mMU6MJ13x6S+Pw==
+  dependencies:
+    cookie "^0.3.1"
+
 locate-path@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/locate-path/-/locate-path-2.0.0.tgz#2b568b265eec944c6d9c0de9c3dbbbca0354cd8e"