feat(create-jest): Add npm init / yarn create initialiser (#14453)

Co-authored-by: Tom Mrazauskas <tom@mrazauskas.de>

.eslintrc.cjs

@@ -357,7 +357,7 @@ module.exports = {
  files: [
  'scripts/*',
  'packages/*/__benchmarks__/test.js',
- 'packages/jest-cli/src/init/index.ts',
+ 'packages/create-jest/src/runCreate.ts',
  'packages/jest-repl/src/cli/runtime-cli.ts',
  ],
  rules: {

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ### Features
 
+- `[create-jest]` Add `npm init` / `yarn create` initialiser for Jest projects ([#14465](https://github.com/jestjs/jest/pull/14453))
+
 ### Fixes
 
 - `[jest-snapshot]` Allow for strings as well as template literals in inline snapshots ([#14465](https://github.com/jestjs/jest/pull/14465))
@@ -13,6 +15,8 @@
 
 ### Chore & Maintenance
 
+- `[jest-cli]` Move internal config initialisation logic to the `create-jest` package ([#14465](https://github.com/jestjs/jest/pull/14453))
+
 ## 29.6.4
 
 ### Fixes

README.md

@@ -131,7 +131,7 @@ If you'd like to learn more about running `jest` through the command line, take
 Based on your project, Jest will ask you a few questions and will create a basic configuration file with a short description for each option:
 
 ```bash
-jest --init
+yarn create jest
 ```
 
 ### Using Babel

docs/GettingStarted.md

@@ -67,8 +67,8 @@ If you'd like to learn more about running `jest` through the command line, take
 
 Based on your project, Jest will ask you a few questions and will create a basic configuration file with a short description for each option:
 
-```bash
-jest --init
+```bash npm2yarn
+npm init jest@latest
 ```
 
 ### Using Babel

package.json

@@ -111,7 +111,7 @@
  "test": "yarn lint && yarn jest",
  "typecheck": "yarn typecheck:examples && yarn typecheck:tests",
  "typecheck:examples": "tsc -p examples/angular --noEmit && tsc -p examples/expect-extend --noEmit && tsc -p examples/typescript --noEmit",
- "typecheck:tests": "tsc -b packages/{babel-jest,babel-plugin-jest-hoist,diff-sequences,expect,expect-utils,jest-circus,jest-cli,jest-config,jest-console,jest-snapshot,jest-util,jest-validate,jest-watcher,jest-worker,pretty-format}/**/__tests__",
+ "typecheck:tests": "tsc -b packages/{babel-jest,babel-plugin-jest-hoist,create-jest,diff-sequences,expect,expect-utils,jest-circus,jest-cli,jest-config,jest-console,jest-snapshot,jest-util,jest-validate,jest-watcher,jest-worker,pretty-format}/**/__tests__",
  "verify-old-ts": "node ./scripts/verifyOldTs.mjs",
  "verify-pnp": "node ./scripts/verifyPnP.mjs",
  "watch": "yarn build:js && node ./scripts/watch.mjs",

packages/create-jest/.npmignore

@@ -0,0 +1,8 @@
+**/__mocks__/**
+**/__tests__/**
+__typetests__
+src
+tsconfig.json
+tsconfig.tsbuildinfo
+api-extractor.json
+.eslintcache

packages/create-jest/README.md

@@ -0,0 +1,11 @@
+# create-jest
+
+> Getting started with Jest with a single command
+
+```bash
+npm init jest@latest
+# Or for Yarn
+yarn create jest
+# Or for pnpm
+pnpm create jest
+```

packages/create-jest/bin/create-jest.js

@@ -0,0 +1,8 @@
+#!/usr/bin/env node
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+require('..').runCLI();

packages/create-jest/package.json

@@ -0,0 +1,42 @@
+{
+ "name": "create-jest",
+ "description": "Create a new Jest project",
+ "version": "29.6.4",
+ "repository": {
+ "type": "git",
+ "url": "https://github.com/jestjs/jest.git",
+ "directory": "packages/create-jest"
+ },
+ "license": "MIT",
+ "bin": "./bin/create-jest.js",
+ "main": "./build/index.js",
+ "types": "./build/index.d.ts",
+ "exports": {
+ ".": {
+ "types": "./build/index.d.ts",
+ "default": "./build/index.js"
+ },
+ "./package.json": "./package.json",
+ "./bin/create-jest": "./bin/create-jest.js"
+ },
+ "dependencies": {
+ "@jest/types": "workspace:^",
+ "chalk": "^4.0.0",
+ "exit": "^0.1.2",
+ "graceful-fs": "^4.2.9",
+ "jest-config": "workspace:^",
+ "jest-util": "workspace:^",
+ "prompts": "^2.0.1"
+ },
+ "engines": {
+ "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+ },
+ "publishConfig": {
+ "access": "public"
+ },
+ "devDependencies": {
+ "@types/exit": "^0.1.30",
+ "@types/graceful-fs": "^4.1.3",
+ "@types/prompts": "^2.0.1"
+ }
+}

packages/jest-cli/src/init/__tests__/init.test.ts → packages/create-jest/src/__tests__/init.test.ts

@@ -10,7 +10,7 @@ import * as path from 'path';
 import {writeFileSync} from 'graceful-fs';
 import * as prompts from 'prompts';
 import {constants} from 'jest-config';
-import init from '../';
+import {runCreate} from '../runCreate';
 
 const {JEST_CONFIG_EXT_ORDER} = constants;
 
@@ -44,7 +44,7 @@ describe('init', () => {
  it('should return the default configuration (an empty config)', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({});
 
- await init(resolveFromFixture('only-package-json'));
+ await runCreate(resolveFromFixture('only-package-json'));
 
  const writtenJestConfigFilename =
  jest.mocked(writeFileSync).mock.calls[0][0];
@@ -71,7 +71,7 @@ describe('init', () => {
  it('should generate empty config with mjs extension', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({});
 
- await init(resolveFromFixture('type-module'));
+ await runCreate(resolveFromFixture('type-module'));
 
  const writtenJestConfigFilename =
  jest.mocked(writeFileSync).mock.calls[0][0];
@@ -93,7 +93,7 @@ describe('init', () => {
  it('should create configuration for {clearMocks: true}', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({clearMocks: true});
 
- await init(resolveFromFixture('only-package-json'));
+ await runCreate(resolveFromFixture('only-package-json'));
 
  const writtenJestConfig = jest.mocked(writeFileSync).mock.calls[0][1];
  const evaluatedConfig = eval(writtenJestConfig as string) as Record<
@@ -107,7 +107,7 @@ describe('init', () => {
  it('should create configuration for {coverage: true}', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({coverage: true});
 
- await init(resolveFromFixture('only-package-json'));
+ await runCreate(resolveFromFixture('only-package-json'));
 
  const writtenJestConfig = jest.mocked(writeFileSync).mock.calls[0][1];
  const evaluatedConfig = eval(writtenJestConfig as string) as Record<
@@ -124,7 +124,7 @@ describe('init', () => {
  it('should create configuration for {coverageProvider: "babel"}', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({coverageProvider: 'babel'});
 
- await init(resolveFromFixture('only-package-json'));
+ await runCreate(resolveFromFixture('only-package-json'));
 
  const writtenJestConfig = jest.mocked(writeFileSync).mock.calls[0][1];
  const evaluatedConfig = eval(writtenJestConfig as string) as Record<
@@ -138,7 +138,7 @@ describe('init', () => {
  it('should create configuration for {coverageProvider: "v8"}', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({coverageProvider: 'v8'});
 
- await init(resolveFromFixture('only-package-json'));
+ await runCreate(resolveFromFixture('only-package-json'));
 
  const writtenJestConfig = jest.mocked(writeFileSync).mock.calls[0][1];
  const evaluatedConfig = eval(writtenJestConfig as string) as Record<
@@ -152,7 +152,7 @@ describe('init', () => {
  it('should create configuration for {environment: "jsdom"}', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({environment: 'jsdom'});
 
- await init(resolveFromFixture('only-package-json'));
+ await runCreate(resolveFromFixture('only-package-json'));
 
  const writtenJestConfig = jest.mocked(writeFileSync).mock.calls[0][1];
  const evaluatedConfig = eval(writtenJestConfig as string) as Record<
@@ -165,7 +165,7 @@ describe('init', () => {
  it('should create configuration for {environment: "node"}', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({environment: 'node'});
 
- await init(resolveFromFixture('only-package-json'));
+ await runCreate(resolveFromFixture('only-package-json'));
 
  const writtenJestConfig = jest.mocked(writeFileSync).mock.calls[0][1];
  const evaluatedConfig = eval(writtenJestConfig as string) as Record<
@@ -178,7 +178,7 @@ describe('init', () => {
  it('should create package.json with configured test command when {scripts: true}', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({scripts: true});
 
- await init(resolveFromFixture('only-package-json'));
+ await runCreate(resolveFromFixture('only-package-json'));
 
  const writtenPackageJson = jest.mocked(writeFileSync).mock.calls[0][1];
  const parsedPackageJson = JSON.parse(writtenPackageJson as string) as {
@@ -196,7 +196,7 @@ describe('init', () => {
  expect.assertions(1);
 
  try {
- await init(resolveFromFixture('no-package-json'));
+ await runCreate(resolveFromFixture('no-package-json'));
  } catch (error) {
  expect((error as Error).message).toMatch(
  'Could not find a "package.json" file in',
@@ -215,7 +215,9 @@ describe('init', () => {
  .mockResolvedValueOnce({continue: true})
  .mockResolvedValueOnce({});
 
- await init(resolveFromFixture(`has-jest-config-file-${extension}`));
+ await runCreate(
+ resolveFromFixture(`has-jest-config-file-${extension}`),
+ );
 
  expect(jest.mocked(prompts).mock.calls[0][0]).toMatchSnapshot();
 
@@ -230,7 +232,9 @@ describe('init', () => {
  it('user answered with "No"', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({continue: false});
 
- await init(resolveFromFixture(`has-jest-config-file-${extension}`));
+ await runCreate(
+ resolveFromFixture(`has-jest-config-file-${extension}`),
+ );
  // return after first prompt
  expect(prompts).toHaveBeenCalledTimes(1);
  });
@@ -243,7 +247,7 @@ describe('init', () => {
  it('user answered with "Yes"', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({useTypescript: true});
 
- await init(resolveFromFixture('test-generated-jest-config-ts'));
+ await runCreate(resolveFromFixture('test-generated-jest-config-ts'));
 
  expect(jest.mocked(prompts).mock.calls[0][0]).toMatchSnapshot();
 
@@ -264,7 +268,7 @@ describe('init', () => {
  it('user answered with "No"', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({useTypescript: false});
 
- await init(resolveFromFixture('test-generated-jest-config-ts'));
+ await runCreate(resolveFromFixture('test-generated-jest-config-ts'));
 
  const jestConfigFileName = jest.mocked(writeFileSync).mock.calls[0][0];
 
@@ -282,7 +286,7 @@ describe('init', () => {
  .mockResolvedValueOnce({continue: true})
  .mockResolvedValueOnce({});
 
- await init(resolveFromFixture('has-jest-config-in-package-json'));
+ await runCreate(resolveFromFixture('has-jest-config-in-package-json'));
 
  expect(jest.mocked(prompts).mock.calls[0][0]).toMatchSnapshot();
 
@@ -296,7 +300,7 @@ describe('init', () => {
  it('should not ask "test script question"', async () => {
  jest.mocked(prompts).mockResolvedValueOnce({});
 
- await init(resolveFromFixture('test-script-configured'));
+ await runCreate(resolveFromFixture('test-script-configured'));
 
  const questions = jest.mocked(prompts).mock.calls[0][0] as Array<
  prompts.PromptObject<string>

packages/create-jest/src/__tests__/tsconfig.json

@@ -0,0 +1,5 @@
+{
+ "extends": "../../../../tsconfig.test.json",
+ "include": ["./**/*"],
+ "references": [{"path": "../../"}]
+}

packages/jest-cli/src/init/errors.ts → packages/create-jest/src/errors.ts

@@ -16,10 +16,7 @@ export class NotFoundPackageJsonError extends Error {
 
 export class MalformedPackageJsonError extends Error {
  constructor(packageJsonPath: string) {
- super(
- `There is malformed json in ${packageJsonPath}\n` +
- 'Fix it, and then run "jest --init"',
- );
+ super(`There is malformed json in ${packageJsonPath}`);
  this.name = '';
  // eslint-disable-next-line @typescript-eslint/no-empty-function
  Error.captureStackTrace(this, () => {});

packages/jest-cli/src/init/generateConfigFile.ts → packages/create-jest/src/generateConfigFile.ts

@@ -7,13 +7,16 @@
 
 import type {Config} from '@jest/types';
 import {defaults, descriptions} from 'jest-config';
+import type {PromptsResults} from './types';
 
 const stringifyOption = (
  option: keyof Config.InitialOptions,
  map: Partial<Config.InitialOptions>,
  linePrefix = '',
 ): string => {
- const optionDescription = ` // ${descriptions[option]}`;
+ const description = descriptions[option];
+ const optionDescription =
+ description != null && description.length > 0 ? ` // ${description}` : '';
  const stringifiedObject = `${option}: ${JSON.stringify(
  map[option],
  null,
@@ -27,7 +30,7 @@ const stringifyOption = (
 };
 
 const generateConfigFile = (
- results: Record<string, unknown>,
+ results: PromptsResults,
  generateEsm = false,
 ): string => {
  const {useTypescript, coverage, coverageProvider, clearMocks, environment} =

packages/create-jest/src/index.ts

@@ -0,0 +1,8 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+export {runCreate, runCLI} from './runCreate';