jestjs · SimenB · May 13, 2020 · May 13, 2020 · May 13, 2020 · May 13, 2020
diff --git a/.eslintrc.js b/.eslintrc.js
@@ -26,6 +26,7 @@ module.exports = {
           'error',
           {argsIgnorePattern: '^_'},
         ],
+        '@typescript-eslint/prefer-ts-expect-error': 'error',
         // Since we do `export =`. Remove for Jest 25
         'import/default': 'off',
         'import/order': 'error',

diff --git a/package.json b/package.json
@@ -73,7 +73,7 @@
     "strip-ansi": "^6.0.0",
     "tempy": "^0.5.0",
     "throat": "^5.0.0",
-    "typescript": "^3.8.2",
+    "typescript": "^3.9.2",
     "which": "^2.0.1"
   },
   "scripts": {

diff --git a/packages/babel-plugin-jest-hoist/src/index.ts b/packages/babel-plugin-jest-hoist/src/index.ts
@@ -113,7 +113,7 @@ FUNCTIONS.mock = args => {
 
     const ids: Set<NodePath<Identifier>> = new Set();
     const parentScope = moduleFactory.parentPath.scope;
-    // @ts-ignore: ReferencedIdentifier is not known on visitors
+    // @ts-expect-error: ReferencedIdentifier is not known on visitors
     moduleFactory.traverse(IDVisitor, {ids});
     for (const id of ids) {
       const {name} = id.node;

diff --git a/packages/jest-circus/src/__tests__/circusItTestError.test.ts b/packages/jest-circus/src/__tests__/circusItTestError.test.ts
@@ -29,21 +29,21 @@ describe('test/it error throwing', () => {
   });
   it(`it throws error with missing callback function`, () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusIt('test2');
     }).toThrowError(
       'Missing second argument. It must be a callback function. Perhaps you want to use `test.todo` for a test placeholder.',
     );
   });
   it(`it throws an error when first argument isn't a string`, () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusIt(() => {});
     }).toThrowError('Invalid first argument, () => {}. It must be a string.');
   });
   it('it throws an error when callback function is not a function', () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusIt('test4', 'test4b');
     }).toThrowError(
       'Invalid second argument, test4b. It must be a callback function.',
@@ -56,21 +56,21 @@ describe('test/it error throwing', () => {
   });
   it(`test throws error with missing callback function`, () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusTest('test6');
     }).toThrowError(
       'Missing second argument. It must be a callback function. Perhaps you want to use `test.todo` for a test placeholder.',
     );
   });
   it(`test throws an error when first argument isn't a string`, () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusTest(() => {});
     }).toThrowError('Invalid first argument, () => {}. It must be a string.');
   });
   it('test throws an error when callback function is not a function', () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusTest('test8', 'test8b');
     }).toThrowError(
       'Invalid second argument, test8b. It must be a callback function.',

diff --git a/packages/jest-circus/src/__tests__/circusItTodoTestError.test.ts b/packages/jest-circus/src/__tests__/circusItTodoTestError.test.ts
@@ -22,7 +22,7 @@ aliasCircusIt();
 describe('test/it.todo error throwing', () => {
   it('todo throws error when given no arguments', () => {
     expect(() => {
-      // @ts-ignore: Testing runtime errors here
+      // @ts-expect-error: Testing runtime errors here
       circusIt.todo();
     }).toThrowError('Todo must be called with only a description.');
   });
@@ -33,7 +33,7 @@ describe('test/it.todo error throwing', () => {
   });
   it('todo throws error when given none string description', () => {
     expect(() => {
-      // @ts-ignore: Testing runtime errors here
+      // @ts-expect-error: Testing runtime errors here
       circusIt.todo(() => {});
     }).toThrowError('Todo must be called with only a description.');
   });

diff --git a/packages/jest-cli/src/__tests__/cli/args.test.ts b/packages/jest-cli/src/__tests__/cli/args.test.ts
@@ -101,11 +101,11 @@ describe('check', () => {
 
 describe('buildArgv', () => {
   it('should return only camelcased args ', () => {
-    // @ts-ignore
+    // @ts-expect-error
     const mockProcessArgv = jest
       .spyOn(process.argv, 'slice')
       .mockImplementation(() => ['--clear-mocks']);
-    // @ts-ignore
+    // @ts-expect-error
     const actual = buildArgv(null);
     expect(actual).not.toHaveProperty('clear-mocks');
     expect(actual).toHaveProperty('clearMocks', true);

diff --git a/packages/jest-cli/src/init/index.ts b/packages/jest-cli/src/init/index.ts
@@ -108,7 +108,7 @@ export default async (
 
   let promptAborted: boolean = false;
 
-  // @ts-ignore: Return type cannot be object - faulty typings
+  // @ts-expect-error: Return type cannot be object - faulty typings
   const results: PromptsResults = await prompts(questions, {
     onCancel: () => {
       promptAborted = true;

diff --git a/packages/jest-config/src/__tests__/getMaxWorkers.test.ts b/packages/jest-config/src/__tests__/getMaxWorkers.test.ts
@@ -39,19 +39,19 @@ describe('getMaxWorkers', () => {
   describe('% based', () => {
     it('50% = 2 workers', () => {
       const argv = {maxWorkers: '50%'};
-      // @ts-ignore: need to fix the typing
+      // @ts-expect-error: need to fix the typing
       expect(getMaxWorkers(argv)).toBe(2);
     });
 
     it('< 0 workers should become 1', () => {
       const argv = {maxWorkers: '1%'};
-      // @ts-ignore: need to fix the typing
+      // @ts-expect-error: need to fix the typing
       expect(getMaxWorkers(argv)).toBe(1);
     });
 
     it("0% shouldn't break", () => {
       const argv = {maxWorkers: '0%'};
-      // @ts-ignore: need to fix the typing
+      // @ts-expect-error: need to fix the typing
       expect(getMaxWorkers(argv)).toBe(1);
     });
   });

diff --git a/packages/jest-config/src/__tests__/readConfig.test.ts b/packages/jest-config/src/__tests__/readConfig.test.ts
@@ -10,7 +10,7 @@ import {readConfig} from '../index';
 test('readConfig() throws when an object is passed without a file path', async () => {
   await expect(
     readConfig(
-      // @ts-ignore
+      // @ts-expect-error
       null /* argv */,
       {} /* packageRootOrConfig */,
       false /* skipArgvConfigOption */,

diff --git a/packages/jest-config/src/__tests__/readConfigs.test.ts b/packages/jest-config/src/__tests__/readConfigs.test.ts
@@ -19,7 +19,7 @@ jest.mock('../readConfigFileAndSetRootDir', () => jest.fn(() => mockResult));
 
 test('readConfigs() throws when called without project paths', async () => {
   await expect(
-    // @ts-ignore
+    // @ts-expect-error
     readConfigs(null /* argv */, [] /* projectPaths */),
   ).rejects.toThrowError('jest: No configuration found for any project.');
 });
@@ -29,7 +29,7 @@ test('readConfigs() loads async config file', async () => {
     rootDir: './',
   }));
   await expect(
-    // @ts-ignore
+    // @ts-expect-error
     readConfigs(
       <Config.Argv>{} /* argv */,
       ['./some-jest-config-file.js'] /* projectPaths */,
@@ -43,7 +43,7 @@ test('readConfigs() reject if async was rejected', async () => {
     throw new Error('Some error');
   });
   await expect(
-    // @ts-ignore
+    // @ts-expect-error
     readConfigs(
       <Config.Argv>{} /* argv */,
       ['./some-jest-config-file.js'] /* projectPaths */,

diff --git a/packages/jest-config/src/normalize.ts b/packages/jest-config/src/normalize.ts
@@ -140,7 +140,7 @@ const setupPreset = (
       }
     } catch (e) {}
 
-    // @ts-ignore: `presetModule` can be null?
+    // @ts-expect-error: `presetModule` can be null?
     preset = require(presetModule);
   } catch (error) {
     if (error instanceof SyntaxError || error instanceof TypeError) {
@@ -943,7 +943,7 @@ export default function normalize(
         });
         break;
     }
-    // @ts-ignore: automock is missing in GlobalConfig, so what
+    // @ts-expect-error: automock is missing in GlobalConfig, so what
     newOptions[key] = value;
     return newOptions;
   }, newOptions);

diff --git a/packages/jest-config/src/readConfigFileAndSetRootDir.ts b/packages/jest-config/src/readConfigFileAndSetRootDir.ts
@@ -9,7 +9,7 @@ import * as path from 'path';
 import {pathToFileURL} from 'url';
 import * as fs from 'graceful-fs';
 import type {Config} from '@jest/types';
-// @ts-ignore: vendored
+// @ts-expect-error: vendored
 import jsonlint from './vendor/jsonlint';
 import {JEST_CONFIG_EXT_JSON, PACKAGE_JSON} from './constants';
 

diff --git a/packages/jest-core/src/watch.ts b/packages/jest-core/src/watch.ts
@@ -504,7 +504,7 @@ const getPluginIdentifier = (plugin: WatchPlugin) =>
   // WatchPlugin is an interface, and it is my understanding interface
   // static fields are not definable anymore, no idea how to circumvent
   // this :-(
-  // @ts-ignore: leave `displayName` be.
+  // @ts-expect-error: leave `displayName` be.
   plugin.constructor.displayName || plugin.constructor.name;
 
 const getPluginKey = (

diff --git a/packages/jest-environment-jsdom/src/__mocks__/index.ts b/packages/jest-environment-jsdom/src/__mocks__/index.ts
@@ -11,15 +11,15 @@ const vm = jest.requireActual('vm');
 const JSDOMEnvironment = jest.createMockFromModule('../index') as jest.Mock;
 
 JSDOMEnvironment.mockImplementation(function (config) {
-  // @ts-ignore
+  // @ts-expect-error
   this.global = {
     JSON,
     console: {},
   };
 
   const globalValues = {...config.globals};
   for (const customGlobalKey in globalValues) {
-    // @ts-ignore
+    // @ts-expect-error
     this.global[customGlobalKey] = globalValues[customGlobalKey];
   }
 });
@@ -28,7 +28,7 @@ JSDOMEnvironment.prototype.runSourceText.mockImplementation(function (
   sourceText: string,
   filename: string,
 ) {
-  // @ts-ignore
+  // @ts-expect-error
   return vm.runInNewContext(sourceText, this.global, {
     displayErrors: false,
     filename,

diff --git a/packages/jest-environment-jsdom/src/index.ts b/packages/jest-environment-jsdom/src/index.ts
@@ -38,7 +38,8 @@ class JSDOMEnvironment implements JestEnvironment {
       virtualConsole: new VirtualConsole().sendTo(options.console || console),
       ...config.testEnvironmentOptions,
     });
-    const global = (this.global = this.dom.window.document.defaultView as Win);
+    const global = (this.global = (this.dom.window.document
+      .defaultView as unknown) as Win);
 
     if (!global) {
       throw new Error('JSDOM did not return a Window object');
@@ -118,7 +119,7 @@ class JSDOMEnvironment implements JestEnvironment {
       this.global.close();
     }
     this.errorEventListener = null;
-    // @ts-ignore
+    // @ts-expect-error
     this.global = null;
     this.dom = null;
     this.fakeTimers = null;

diff --git a/packages/jest-environment-node/src/__tests__/node_environment.test.ts b/packages/jest-environment-node/src/__tests__/node_environment.test.ts
@@ -39,7 +39,7 @@ describe('NodeEnvironment', () => {
     const timer2 = env1.global.setInterval(() => {}, 0);
 
     [timer1, timer2].forEach(timer => {
-      // @ts-ignore
+      // @ts-expect-error
       expect(timer.id).not.toBeUndefined();
       expect(typeof timer.ref).toBe('function');
       expect(typeof timer.unref).toBe('function');

diff --git a/packages/jest-fake-timers/src/legacyFakeTimers.ts b/packages/jest-fake-timers/src/legacyFakeTimers.ts
@@ -366,10 +366,11 @@ export default class FakeTimers<TimerRef> {
 
   private _createMocks() {
     const fn = (impl: Function) =>
-      // @ts-ignore TODO: figure out better typings here
+      // @ts-expect-error TODO: figure out better typings here
       this._moduleMocker.fn().mockImplementation(impl);
 
     const promisifiableFakeSetTimeout = fn(this._fakeSetTimeout.bind(this));
+    // @ts-expect-error TODO: figure out better typings here
     promisifiableFakeSetTimeout[util.promisify.custom] = (
       delay?: number,
       arg?: unknown,
@@ -382,8 +383,11 @@ export default class FakeTimers<TimerRef> {
       clearInterval: fn(this._fakeClearTimer.bind(this)),
       clearTimeout: fn(this._fakeClearTimer.bind(this)),
       nextTick: fn(this._fakeNextTick.bind(this)),
+      // @ts-expect-error TODO: figure out better typings here
       setImmediate: fn(this._fakeSetImmediate.bind(this)),
+      // @ts-expect-error TODO: figure out better typings here
       setInterval: fn(this._fakeSetInterval.bind(this)),
+      // @ts-expect-error TODO: figure out better typings here
       setTimeout: promisifiableFakeSetTimeout,
     };
   }

diff --git a/packages/jest-fake-timers/src/modernFakeTimers.ts b/packages/jest-fake-timers/src/modernFakeTimers.ts
@@ -81,7 +81,7 @@ export default class FakeTimers {
 
   runAllTicks(): void {
     if (this._checkFakeTimers()) {
-      // @ts-ignore
+      // @ts-expect-error
       this._clock.runMicrotasks();
     }
   }

diff --git a/packages/jest-haste-map/src/index.ts b/packages/jest-haste-map/src/index.ts
@@ -26,7 +26,7 @@ import HasteModuleMap, {
 import nodeCrawl = require('./crawlers/node');
 import normalizePathSep from './lib/normalizePathSep';
 import watchmanCrawl = require('./crawlers/watchman');
-// @ts-ignore: not converted to TypeScript - it's a fork: https://github.com/facebook/jest/pull/5387
+// @ts-expect-error: not converted to TypeScript - it's a fork: https://github.com/facebook/jest/pull/5387
 import WatchmanWatcher from './lib/WatchmanWatcher';
 import FSEventsWatcher = require('./lib/FSEventsWatcher');
 import * as fastPath from './lib/fast_path';
@@ -513,7 +513,6 @@ class HasteMap extends EventEmitter {
         error.stack = ''; // Remove stack for stack-less errors.
       }
 
-      // @ts-ignore: checking error code is OK if error comes from "fs".
       if (!['ENOENT', 'EACCES'].includes(error.code)) {
         throw error;
       }
@@ -677,9 +676,9 @@ class HasteMap extends EventEmitter {
   private _cleanup() {
     const worker = this._worker;
 
-    // @ts-ignore
+    // @ts-expect-error
     if (worker && typeof worker.end === 'function') {
-      // @ts-ignore
+      // @ts-expect-error
       worker.end();
     }
 
@@ -701,7 +700,7 @@ class HasteMap extends EventEmitter {
       if ((options && options.forceInBand) || this._options.maxWorkers <= 1) {
         this._worker = {getSha1, worker};
       } else {
-        // @ts-ignore: assignment of a worker with custom properties.
+        // @ts-expect-error: assignment of a worker with custom properties.
         this._worker = new Worker(require.resolve('./worker'), {
           exposedMethods: ['getSha1', 'worker'],
           maxRetries: 3,
@@ -789,7 +788,7 @@ class HasteMap extends EventEmitter {
     let mustCopy = true;
 
     const createWatcher = (root: Config.Path): Promise<Watcher> => {
-      // @ts-ignore: TODO how? "Cannot use 'new' with an expression whose type lacks a call or construct signature."
+      // @ts-expect-error: TODO how? "Cannot use 'new' with an expression whose type lacks a call or construct signature."
       const watcher = new Watcher(root, {
         dot: false,
         glob: extensions.map(extension => '**/*.' + extension),
@@ -1035,7 +1034,7 @@ class HasteMap extends EventEmitter {
   }
 
   end(): Promise<void> {
-    // @ts-ignore: TODO TS cannot decide if `setInterval` and `clearInterval` comes from NodeJS or the DOM
+    // @ts-expect-error: TODO TS cannot decide if `setInterval` and `clearInterval` comes from NodeJS or the DOM
     clearInterval(this._changeInterval);
     if (!this._watchers.length) {
       return Promise.resolve();

diff --git a/packages/jest-haste-map/src/lib/FSEventsWatcher.ts b/packages/jest-haste-map/src/lib/FSEventsWatcher.ts
@@ -11,9 +11,10 @@ import {EventEmitter} from 'events';
 import * as fs from 'graceful-fs';
 import anymatch, {Matcher} from 'anymatch';
 import micromatch = require('micromatch');
-// @ts-ignore no types
+// @ts-expect-error no types
 import walker from 'walker';
 
+// eslint-disable-next-line @typescript-eslint/prefer-ts-expect-error
 // @ts-ignore: this is for CI which runs linux and might not have this
 let fsevents: typeof import('fsevents') | null = null;
 try {

diff --git a/packages/jest-jasmine2/src/__tests__/Suite.test.ts b/packages/jest-jasmine2/src/__tests__/Suite.test.ts
@@ -19,7 +19,7 @@ describe('Suite', () => {
 
   it("doesn't throw on addExpectationResult when there are no children", () => {
     expect(() => {
-      // @ts-ignore
+      // @ts-expect-error
       suite.addExpectationResult();
     }).not.toThrow();
   });