chore: migrate jest-cli to TypeScript (#8024)

Author: SimenB

CHANGELOG.md

@@ -84,6 +84,8 @@
 - `[@jest/source-map]`: Extract `getCallsite` function from `jest-util` into a new separate package ([#8029](https://github.com/facebook/jest/pull/8029))
 - `[@jest/console]`: Extract custom `console` implementations from `jest-util` into a new separate package ([#8030](https://github.com/facebook/jest/pull/8030))
 - `[docs]`: Improve runAllTimers doc (it exhausts the micro-task queue) ([#8031](https://github.com/facebook/jest/pull/8031))
+- `[jest-cli]`: Migrate to TypeScript ([#8024](https://github.com/facebook/jest/pull/8024))
+- `[jest]`: Migrate to TypeScript ([#8024](https://github.com/facebook/jest/pull/8024))
 
 ### Performance
 

e2e/__tests__/__snapshots__/showConfig.test.ts.snap

@@ -100,6 +100,7 @@ exports[`--showConfig outputs config info and exits 1`] = `
     "filter": null,
     "globalSetup": null,
     "globalTeardown": null,
+    "json": false,
     "listTests": false,
     "maxConcurrency": 5,
     "maxWorkers": "[maxWorkers]",

e2e/__tests__/runProgramatically.test.ts renamed to e2e/__tests__/runProgrammatically.test.ts

@@ -9,7 +9,7 @@ import {resolve} from 'path';
 
 import {run} from '../Utils';
 
-const dir = resolve(__dirname, '..', 'run-programatically');
+const dir = resolve(__dirname, '..', 'run-programmatically');
 
 test('run Jest programatically', () => {
   const {stdout} = run(`node index.js --version`, dir);

e2e/run-programatically/index.js renamed to e2e/run-programmatically/index.js

@@ -0,0 +1,6 @@
+{
+  "name": "run-programmatically",
+  "version": "1.0.0",
+  "dependencies": {},
+  "jest": {}
+}

e2e/run-programmatically/package.json

@@ -3,8 +3,10 @@
   "description": "Delightful JavaScript Testing.",
   "version": "24.1.0",
   "main": "build/index.js",
+  "types": "build/index.d.ts",
   "dependencies": {
     "@jest/core": "^24.1.0",
+    "@jest/types": "^24.1.0",
     "chalk": "^2.0.1",
     "exit": "^0.1.2",
     "import-local": "^2.0.0",

packages/jest-cli/package.json

@@ -6,55 +6,56 @@
  *
  */
 
-'use strict';
-
-import type {Argv} from 'types/Argv';
+import {Config} from '@jest/types';
 import {check} from '../../cli/args';
 import {buildArgv} from '../../cli';
 
 describe('check', () => {
   it('returns true if the arguments are valid', () => {
-    const argv: Argv = {};
+    const argv = {} as Config.Argv;
     expect(check(argv)).toBe(true);
   });
 
   it('raises an exception if runInBand and maxWorkers are both specified', () => {
-    const argv: Argv = {maxWorkers: 2, runInBand: true};
+    const argv = {maxWorkers: 2, runInBand: true} as Config.Argv;
     expect(() => check(argv)).toThrow(
       'Both --runInBand and --maxWorkers were specified',
     );
   });
 
   it('raises an exception if onlyChanged and watchAll are both specified', () => {
-    const argv: Argv = {onlyChanged: true, watchAll: true};
+    const argv = {onlyChanged: true, watchAll: true} as Config.Argv;
     expect(() => check(argv)).toThrow(
       'Both --onlyChanged and --watchAll were specified',
     );
   });
 
   it('raises an exception when lastCommit and watchAll are both specified', () => {
-    const argv: Argv = {lastCommit: true, watchAll: true};
+    const argv = {lastCommit: true, watchAll: true} as Config.Argv;
     expect(() => check(argv)).toThrow(
       'Both --lastCommit and --watchAll were specified',
     );
   });
 
   it('raises an exception if findRelatedTests is specified with no file paths', () => {
-    const argv: Argv = {_: [], findRelatedTests: true};
+    const argv = {
+      _: [] as Array<string>,
+      findRelatedTests: true,
+    } as Config.Argv;
     expect(() => check(argv)).toThrow(
       'The --findRelatedTests option requires file paths to be specified',
     );
   });
 
   it('raises an exception if maxWorkers is specified with no number', () => {
-    const argv: Argv = {maxWorkers: undefined};
+    const argv = ({maxWorkers: undefined} as unknown) as Config.Argv;
     expect(() => check(argv)).toThrow(
       'The --maxWorkers (-w) option requires a number to be specified',
     );
   });
 
   it('raises an exception if config is not a valid JSON string', () => {
-    const argv: Argv = {config: 'x:1'};
+    const argv = {config: 'x:1'} as Config.Argv;
     expect(() => check(argv)).toThrow(
       'The --config option requires a JSON string literal, or a file path with a .js or .json extension',
     );
@@ -63,9 +64,11 @@ describe('check', () => {
 
 describe('buildArgv', () => {
   it('should return only camelcased args ', () => {
+    // @ts-ignore
     const mockProcessArgv = jest
       .spyOn(process.argv, 'slice')
       .mockImplementation(() => ['--clear-mocks']);
+    // @ts-ignore
     const actual = buildArgv(null);
     expect(actual).not.toHaveProperty('clear-mocks');
     expect(actual).toHaveProperty('clearMocks', true);