chore: migrate jest-config to TypeScript (#7944)

packages/jest-config/package.json

@@ -8,8 +8,10 @@
   },
   "license": "MIT",
   "main": "build/index.js",
+  "types": "build/index.d.ts",
   "dependencies": {
     "@babel/core": "^7.1.0",
+    "@jest/types": "^24.1.0",
     "babel-jest": "^24.1.0",
     "chalk": "^2.0.1",
     "glob": "^7.1.1",

packages/jest-config/src/Defaults.js → packages/jest-config/src/Defaults.ts

@@ -3,19 +3,16 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @flow
  */
 
-import type {DefaultOptions} from 'types/Config';
-
+import {Config} from '@jest/types';
 import {replacePathSepForRegex} from 'jest-regex-util';
 import {NODE_MODULES} from './constants';
 import getCacheDirectory from './getCacheDirectory';
 
 const NODE_MODULES_REGEXP = replacePathSepForRegex(NODE_MODULES);
 
-export default ({
+const defaultOptions: Config.DefaultOptions = {
   automock: false,
   bail: 0,
   browser: false,
@@ -83,4 +80,6 @@ export default ({
   watch: false,
   watchPathIgnorePatterns: [],
   watchman: true,
-}: DefaultOptions);
+};
+
+export default defaultOptions;

packages/jest-config/src/Deprecated.js → packages/jest-config/src/Deprecated.ts

@@ -3,14 +3,12 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @flow
  */
 
 import chalk from 'chalk';
 import prettyFormat from 'pretty-format';
 
-const format = (value: mixed) => prettyFormat(value, {min: true});
+const format = (value: unknown) => prettyFormat(value, {min: true});
 
 export default {
   mapCoverage: () => `  Option ${chalk.bold(
@@ -20,7 +18,7 @@ export default {
   Please update your configuration.`,
 
   preprocessorIgnorePatterns: (options: {
-    preprocessorIgnorePatterns: Array<string>,
+    preprocessorIgnorePatterns: Array<string>;
   }) => `  Option ${chalk.bold(
     '"preprocessorIgnorePatterns"',
   )} was replaced by ${chalk.bold(
@@ -37,7 +35,7 @@ export default {
   Please update your configuration.`,
 
   scriptPreprocessor: (options: {
-    scriptPreprocessor: string,
+    scriptPreprocessor: string;
   }) => `  Option ${chalk.bold(
     '"scriptPreprocessor"',
   )} was replaced by ${chalk.bold(
@@ -53,8 +51,8 @@ export default {
 
   Please update your configuration.`,
 
-  setupTestFrameworkScriptFile: (options: {
-    setupTestFrameworkScriptFile: Array<string>,
+  setupTestFrameworkScriptFile: (_options: {
+    setupTestFrameworkScriptFile: Array<string>;
   }) => `  Option ${chalk.bold(
     '"setupTestFrameworkScriptFile"',
   )} was replaced by configuration ${chalk.bold(
@@ -64,7 +62,7 @@ export default {
   Please update your configuration.`,
 
   testPathDirs: (options: {
-    testPathDirs: Array<string>,
+    testPathDirs: Array<string>;
   }) => `  Option ${chalk.bold('"testPathDirs"')} was replaced by ${chalk.bold(
     '"roots"',
   )}.

packages/jest-config/src/Descriptions.js → packages/jest-config/src/Descriptions.ts

@@ -3,11 +3,11 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @flow
  */
 
-export default ({
+import {Config} from '@jest/types';
+
+const descriptions: {[key in keyof Config.InitialOptions]: string} = {
   automock: 'All imported modules in your tests should be mocked automatically',
   bail: 'Stop running tests after `n` failures',
   browser: 'Respect "browser" field in package.json when resolving modules',
@@ -91,4 +91,6 @@ export default ({
   watchPathIgnorePatterns:
     'An array of regexp patterns that are matched against all source file paths before re-running tests in watch mode',
   watchman: 'Whether to use watchman for file crawling',
-}: {[string]: string});
+};
+
+export default descriptions;

packages/jest-config/src/ReporterValidationErrors.js → packages/jest-config/src/ReporterValidationErrors.ts

@@ -6,8 +6,8 @@
  * @flow
  */
 
-import type {ReporterConfig} from 'types/Config';
-
+import {Config} from '@jest/types';
+// @ts-ignore: Not migrated to TS
 import {ValidationError} from 'jest-validate';
 import chalk from 'chalk';
 import getType from 'jest-get-type';
@@ -26,7 +26,7 @@ const ERROR = `${BULLET}Reporter Validation Error`;
  */
 export function createReporterError(
   reporterIndex: number,
-  reporterValue: Array<ReporterConfig> | string,
+  reporterValue: Array<Config.ReporterConfig> | string,
 ): ValidationError {
   const errorMessage =
     `  Reporter at index ${reporterIndex} must be of type:\n` +
@@ -38,7 +38,7 @@ export function createReporterError(
 }
 
 export function createArrayReporterError(
-  arrayReporter: ReporterConfig,
+  arrayReporter: Config.ReporterConfig,
   reporterIndex: number,
   valueIndex: number,
   value: string | Object,
@@ -63,7 +63,7 @@ export function createArrayReporterError(
 }
 
 export function validateReporters(
-  reporterConfig: Array<ReporterConfig | string>,
+  reporterConfig: Array<Config.ReporterConfig | string>,
 ): boolean {
   return reporterConfig.every((reporter, index) => {
     if (Array.isArray(reporter)) {
@@ -77,7 +77,7 @@ export function validateReporters(
 }
 
 function validateArrayReporter(
-  arrayReporter: ReporterConfig,
+  arrayReporter: Config.ReporterConfig,
   reporterIndex: number,
 ) {
   const [path, options] = arrayReporter;

packages/jest-config/src/ValidConfig.js → packages/jest-config/src/ValidConfig.ts

@@ -3,21 +3,19 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @flow
  */
 
-import type {InitialOptions} from 'types/Config';
-
+import {Config} from '@jest/types';
 import {replacePathSepForRegex} from 'jest-regex-util';
+// @ts-ignore: Not migrated to TS
 import {multipleValidOptions} from 'jest-validate';
 import {NODE_MODULES} from './constants';
 
 const NODE_MODULES_REGEXP = replacePathSepForRegex(NODE_MODULES);
 
-export default ({
+const initialOptions: Config.InitialOptions = {
   automock: false,
-  bail: (multipleValidOptions(false, 0): any),
+  bail: multipleValidOptions(false, 0),
   browser: false,
   cache: true,
   cacheDirectory: '/tmp/user/jest',
@@ -40,6 +38,7 @@ export default ({
       statements: 100,
     },
   },
+  // @ts-ignore: Missing from initial options... https://github.com/facebook/jest/pull/7923
   cwd: '/root',
   dependencyExtractor: '<rootDir>/dependencyExtractor.js',
   displayName: 'project-name',
@@ -135,4 +134,6 @@ export default ({
     ],
   ],
   watchman: true,
-}: InitialOptions);
+};
+
+export default initialOptions;

packages/jest-config/src/__tests__/getMaxWorkers.test.js → packages/jest-config/src/__tests__/getMaxWorkers.test.ts

@@ -38,16 +38,19 @@ describe('getMaxWorkers', () => {
   describe('% based', () => {
     it('50% = 2 workers', () => {
       const argv = {maxWorkers: '50%'};
+      // @ts-ignore: 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
       expect(getMaxWorkers(argv)).toBe(1);
     });
 
     it("0% shouldn't break", () => {
       const argv = {maxWorkers: '0%'};
+      // @ts-ignore: need to fix the typing
       expect(getMaxWorkers(argv)).toBe(1);
     });
   });

packages/jest-config/src/__tests__/readConfig.test.js → packages/jest-config/src/__tests__/readConfig.test.ts

@@ -5,6 +5,7 @@ import {readConfig} from '../index';
 test('readConfig() throws when an object is passed without a file path', () => {
   expect(() => {
     readConfig(
+      // @ts-ignore
       null /* argv */,
       {} /* packageRootOrConfig */,
       false /* skipArgvConfigOption */,

packages/jest-config/src/__tests__/readConfigs.test.js → packages/jest-config/src/__tests__/readConfigs.test.ts

@@ -4,6 +4,7 @@ import {readConfigs} from '../index';
 
 test('readConfigs() throws when called without project paths', () => {
   expect(() => {
+    // @ts-ignore
     readConfigs(null /* argv */, [] /* projectPaths */);
   }).toThrowError('jest: No configuration found for any project.');
 });

packages/jest-config/src/__tests__/resolveConfigPath.test.js → packages/jest-config/src/__tests__/resolveConfigPath.test.ts

@@ -3,8 +3,6 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @flow
  */
 
 import os from 'os';

packages/jest-config/src/__tests__/setFromArgv.test.js → packages/jest-config/src/__tests__/setFromArgv.test.ts

@@ -6,16 +6,17 @@
  *
  */
 
+import {Config} from '@jest/types';
 import setFromArgv from '../setFromArgv';
 
 test('maps special values to valid options', () => {
-  const options = {};
+  const options = {} as Config.InitialOptions;
   const argv = {
     coverage: true,
     env: 'node',
     json: true,
     watchAll: true,
-  };
+  } as Config.Argv;
 
   expect(setFromArgv(options, argv)).toMatchObject({
     collectCoverage: true,
@@ -27,12 +28,12 @@ test('maps special values to valid options', () => {
 });
 
 test('maps regular values to themselves', () => {
-  const options = {};
+  const options = {} as Config.InitialOptions;
   const argv = {
     collectCoverageOnlyFrom: ['a', 'b'],
     coverageDirectory: 'covDir',
     watchman: true,
-  };
+  } as Config.Argv;
 
   expect(setFromArgv(options, argv)).toMatchObject({
     collectCoverageOnlyFrom: ['a', 'b'],
@@ -42,11 +43,11 @@ test('maps regular values to themselves', () => {
 });
 
 test('works with string objects', () => {
-  const options = {};
+  const options = {} as Config.InitialOptions;
   const argv = {
     moduleNameMapper: '{"types/(.*)": "<rootDir>/src/types/$1"}',
     transform: '{"*.js": "<rootDir>/transformer"}',
-  };
+  } as Config.Argv;
   expect(setFromArgv(options, argv)).toMatchObject({
     moduleNameMapper: {
       'types/(.*)': '<rootDir>/src/types/$1',
@@ -58,10 +59,10 @@ test('works with string objects', () => {
 });
 
 test('explicit flags override those from --config', () => {
-  const options = {};
+  const options = {} as Config.InitialOptions;
   const argv = {
     config: '{"watch": false}',
     watch: true,
-  };
+  } as Config.Argv;
   expect(setFromArgv(options, argv)).toMatchObject({watch: true});
 });

packages/jest-config/src/constants.js → packages/jest-config/src/constants.ts

@@ -3,8 +3,6 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @flow
  */
 
 import path from 'path';

packages/jest-config/src/getCacheDirectory.js → packages/jest-config/src/getCacheDirectory.ts

@@ -3,13 +3,10 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @flow
  */
 
-const path = require('path');
-const os = require('os');
-
+import path from 'path';
+import os from 'os';
 import {sync as realpath} from 'realpath-native';
 
 const getCacheDirectory = () => {

packages/jest-config/src/getMaxWorkers.js → packages/jest-config/src/getMaxWorkers.ts

@@ -3,23 +3,24 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @flow
  */
 
-import type {Argv} from 'types/Argv';
-
 import os from 'os';
+import {Config} from '@jest/types';
 
-export default function getMaxWorkers(argv: Argv): number {
+export default function getMaxWorkers(
+  argv: Partial<Pick<Config.Argv, 'maxWorkers' | 'runInBand' | 'watch'>>,
+): number {
   if (argv.runInBand) {
     return 1;
   } else if (argv.maxWorkers) {
-    const parsed = parseInt(argv.maxWorkers, 10);
+    // TODO: How to type this properly? Should probably use `coerce` from `yargs`
+    const maxWorkers = (argv.maxWorkers as unknown) as number | string;
+    const parsed = parseInt(maxWorkers as string, 10);
 
     if (
-      typeof argv.maxWorkers === 'string' &&
-      argv.maxWorkers.trim().endsWith('%') &&
+      typeof maxWorkers === 'string' &&
+      maxWorkers.trim().endsWith('%') &&
       parsed > 0 &&
       parsed <= 100
     ) {