Babel 7

CHANGELOG.md

@@ -43,6 +43,7 @@
 - `[jest-mock]` [**BREAKING**] Fix bugs with mock/spy result tracking of recursive functions ([#6381](https://github.com/facebook/jest/pull/6381))
 - `[jest-haste-map]` [**BREAKING**] Recover files correctly after haste name collisions are fixed ([#7329](https://github.com/facebook/jest/pull/7329))
 - `[pretty-format]` [**BREAKING**] Omit non-enumerable symbol properties ([#7448](https://github.com/facebook/jest/pull/7448))
+- `[*]` [**BREAKING**] Upgrade to Babel 7, dropping support for Babel 6 ([#7016](https://github.com/facebook/jest/pull/7016))
 - `[expect]` Standardize file naming in `expect` ([#7306](https://github.com/facebook/jest/pull/7306))
 - `[jest-each]` Add empty array validation check ([#7249](https://github.com/facebook/jest/pull/7249))
 - `[jest-cli]` Interrupt tests if interactive watch plugin key is pressed ([#7222](https://github.com/facebook/jest/pull/7222))

README.md

@@ -101,39 +101,22 @@ If you'd like to learn more about running `jest` through the command line, take
 
 ### Using Babel
 
-[Babel](http://babeljs.io/) is automatically handled by Jest using `babel-jest`. You don't need install anything extra for using Babel.
+To use [Babel](http://babeljs.io/), install the `babel-jest` and `@babel/core` packages:
 
-> Note: If you are using Babel version 7 then you need to install `babel-jest`, `babel-core@^7.0.0-bridge.0` and `@babel/core` with the following command:
->
-> ```bash
-> yarn add --dev babel-jest babel-core@^7.0.0-bridge.0 @babel/core regenerator-runtime
-> ```
+```bash
+yarn add --dev babel-jest @babel/core
+```
 
-Don't forget to add a [`.babelrc`](https://babeljs.io/docs/usage/babelrc/) file in your project's root folder. For example, if you are using ES6 and [React.js](https://reactjs.org) with the [`babel-preset-env`](https://babeljs.io/docs/plugins/preset-env/) and [`babel-preset-react`](https://babeljs.io/docs/plugins/preset-react/) presets:
+Don't forget to add a [`babel.config.js`](https://babeljs.io/docs/en/config-files) file in your project's root folder. For example, if you are using ES6 and [React.js](https://reactjs.org) with the [`@babel/preset-env`](https://babeljs.io/docs/en/babel-preset-env) and [`@babel/preset-react`](https://babeljs.io/docs/en/babel-preset-react) presets:
 
-```json
-{
-  "presets": ["env", "react"]
-}
+```js
+module.exports = {
+  presets: ['@babel/preset-env', '@babel/preset-react'],
+};
 ```
 
 You are now set up to use all ES6 features and React specific syntax.
 
-> Note: If you are using a more complicated Babel configuration, using Babel's `env` option, keep in mind that Jest will automatically define `NODE_ENV` as `test`. It will not use `development` section like Babel does by default when no `NODE_ENV` is set.
-
-> Note: If you've turned off transpilation of ES modules with the option `{ "modules": false }`, you have to make sure to turn this on in your test environment.
-
-```json
-{
-  "presets": [["env", {"modules": false}], "react"],
-  "env": {
-    "test": {
-      "presets": [["env"], "react"]
-    }
-  }
-}
-```
-
 > Note: `babel-jest` is automatically installed when installing Jest and will automatically transform files if a babel configuration exists in your project. To avoid this behavior, you can explicitly reset the `transform` configuration option:
 
 ```json

babel.config.js

@@ -0,0 +1,19 @@
+// Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
+
+module.exports = {
+  babelrcRoots: ['examples/*'],
+  plugins: [
+    ['@babel/plugin-transform-modules-commonjs', {allowTopLevelThis: true}],
+    '@babel/plugin-transform-strict-mode',
+  ],
+  presets: [
+    [
+      '@babel/preset-env',
+      {
+        shippedProposals: true,
+        targets: {node: 6},
+      },
+    ],
+    '@babel/preset-flow',
+  ],
+};

docs/Es6ClassMocks.md

@@ -227,7 +227,7 @@ jest.mock('./sound-player', () => {
 });
 ```
 
-This will throw **_TypeError: \_soundPlayer2.default is not a constructor_**, unless the code is transpiled to ES5, e.g. by babel-preset-env. (ES5 doesn't have arrow functions nor classes, so both will be transpiled to plain functions.)
+This will throw **_TypeError: \_soundPlayer2.default is not a constructor_**, unless the code is transpiled to ES5, e.g. by `@babel/preset-env`. (ES5 doesn't have arrow functions nor classes, so both will be transpiled to plain functions.)
 
 ## Keeping track of usage (spying on the mock)
 

docs/GettingStarted.md

@@ -81,44 +81,22 @@ jest --init
 
 ### Using Babel
 
-To use [Babel](http://babeljs.io/), install the `babel-jest` and `regenerator-runtime` packages via `yarn`:
+To use [Babel](http://babeljs.io/), install the `babel-jest` and `@babel/core` packages via `yarn`:
 
 ```bash
-yarn add --dev babel-jest babel-core regenerator-runtime
+yarn add --dev babel-jest @babel/core
 ```
 
-Or `npm`:
+Don't forget to add a [`babel.config.js`](https://babeljs.io/docs/en/config-files) file in your project's root folder. For example, if you are using ES6 and [React.js](https://reactjs.org) with the [`@babel/preset-env`](https://babeljs.io/docs/en/babel-preset-env) and [`@babel/preset-react`](https://babeljs.io/docs/en/babel-preset-react) presets:
 
-```bash
-npm install --save-dev babel-jest babel-core regenerator-runtime
-```
-
-> Note: If you are using Babel version 7 then you need to install `babel-jest`, `babel-core@^7.0.0-bridge.0` and `@babel/core` with the following command or its `npm` equivalent:
->
-> ```bash
-> yarn add --dev babel-jest babel-core@^7.0.0-bridge.0 @babel/core regenerator-runtime
-> ```
->
-> You will need to use `babel.config.js` in order to transpile `node_modules`. See https://babeljs.io/docs/en/next/config-files for more information.
->
-> You can also see the example in the Jest repository: https://github.com/facebook/jest/tree/master/examples/babel-7
-
-_Note: Explicitly installing `regenerator-runtime` is not needed if you use `npm` 3 or 4 or Yarn_
-
-Don't forget to add a [`.babelrc`](https://babeljs.io/docs/usage/babelrc/) file in your project's root folder. For example, if you are using ES6 and [React.js](https://facebook.github.io/react/) with the [`babel-preset-env`](https://babeljs.io/docs/plugins/preset-env/) and [`babel-preset-react`](https://babeljs.io/docs/plugins/preset-react/) presets:
-
-```json
-{
-  "presets": ["env", "react"]
-}
+```js
+module.exports = {
+  presets: ['@babel/preset-env', '@babel/preset-react'],
+};
 ```
 
 You are now set up to use all ES6 features and React specific syntax.
 
-> Note: If you are using a more complicated Babel configuration, using Babel's `env` option, keep in mind that Jest will automatically define `NODE_ENV` as `test` **if not already set** to something else. It will not use `development` section like Babel does by default when no `NODE_ENV` is set.
-
-> Note: If you've turned off transpilation of ES6 modules with the option `{ "modules": false }`, you have to make sure to turn this on in your test environment.
-
 ```json
 {
   "presets": [["env", {"modules": false}], "react"],

docs/Troubleshooting.md

@@ -132,7 +132,7 @@ If you are using Facebook's [`create-react-app`](https://github.com/facebookincu
 
 ## Caching Issues
 
-The transform script was changed or babel was updated and the changes aren't being recognized by Jest?
+The transform script was changed or Babel was updated and the changes aren't being recognized by Jest?
 
 Retry with [`--no-cache`](CLI.md#cache). Jest caches transformed module files to speed up test execution. If you are using your own custom transformer, consider adding a `getCacheKey` function to it: [getCacheKey in Relay](https://github.com/facebook/relay/blob/58cf36c73769690f0bbf90562707eadb062b029d/scripts/jest/preprocessor.js#L56-L61).
 

docs/TutorialAsync.md

@@ -108,7 +108,7 @@ it('works with async/await and resolves', async () => {
 });
 ```
 
-To enable async/await in your project, install [`babel-preset-env`](http://babeljs.io/docs/plugins/preset-env/) and enable the feature in your `.babelrc` file.
+To enable async/await in your project, install [`@babel/preset-env`](https://babeljs.io/docs/en/babel-preset-env) and enable the feature in your `babel.config.js` file.
 
 ## Error handling
 

docs/TutorialReact.md

@@ -24,7 +24,7 @@ If you have an existing application you'll need to install a few packages to mak
 Run
 
 ```bash
-yarn add --dev jest babel-jest babel-preset-env babel-preset-react react-test-renderer
+yarn add --dev jest babel-jest @babel/preset-env @babel/preset-react react-test-renderer
 ```
 
 Your `package.json` should look something like this (where `<current-version>` is the actual latest version number for the package). Please add the scripts and jest configuration entries:
@@ -36,9 +36,9 @@ Your `package.json` should look something like this (where `<current-version>` i
     "react-dom": "<current-version>"
   },
   "devDependencies": {
+    "@babel/preset-env": "<current-version>",
+    "@babel/preset-react": "<current-version>",
     "babel-jest": "<current-version>",
-    "babel-preset-env": "<current-version>",
-    "babel-preset-react": "<current-version>",
     "jest": "<current-version>",
     "react-test-renderer": "<current-version>"
   },
@@ -47,11 +47,11 @@ Your `package.json` should look something like this (where `<current-version>` i
   }
 ```
 
-```json
-// .babelrc
-{
-  "presets": ["env", "react"]
-}
+```js
+// babel.config.js
+module.exports = {
+  presets: ['@babel/preset-env', '@babel/preset-react'],
+};
 ```
 
 **And you're good to go!**
@@ -309,23 +309,22 @@ If you need more advanced functionality, you can also build your own transformer
 // custom-transformer.js
 'use strict';
 
-const babel = require('babel-core');
+const {transform} = require('@babel/core');
 const jestPreset = require('babel-preset-jest');
 
 module.exports = {
   process(src, filename) {
-    if (babel.util.canCompile(filename)) {
-      return babel.transform(src, {
-        filename,
-        presets: [jestPreset],
-      });
-    }
-    return src;
+    const result = transform(src, {
+      filename,
+      presets: [jestPreset],
+    });
+
+    return result ? result.code : src;
   },
 };
 ```
 
-Don't forget to install the `babel-core` and `babel-preset-jest` packages for this example to work.
+Don't forget to install the `@babel/core` and `babel-preset-jest` packages for this example to work.
 
 To make this work with Jest you need to update your Jest configuration with this: `"transform": {"\\.js$": "path/to/custom-transformer.js"}`.
 

docs/TutorialReactNative.md

@@ -134,7 +134,7 @@ The preset sets up the environment and is very opinionated and based on what we
 
 ### transformIgnorePatterns customization
 
-The [`transformIgnorePatterns`](configuration.html#transformignorepatterns-array-string) option can be used to whitelist or blacklist files from being transformed with babel. Many react-native npm modules unfortunately don't pre-compile their source code before publishing.
+The [`transformIgnorePatterns`](configuration.html#transformignorepatterns-array-string) option can be used to whitelist or blacklist files from being transformed with Babel. Many react-native npm modules unfortunately don't pre-compile their source code before publishing.
 
 By default the jest-react-native preset only processes the project's own source files and react-native. If you have npm dependencies that have to be transformed you can customize this configuration option by whitelisting modules other than react-native:
 

e2e/__tests__/__snapshots__/coverage_report.test.js.snap

@@ -46,16 +46,16 @@ exports[`generates coverage when using the testRegex config param  1`] = `
 "-------------------------------------|----------|----------|----------|----------|-------------------|
 File                                 |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
 -------------------------------------|----------|----------|----------|----------|-------------------|
-All files                           </> |    56.52</> |        0</> |       50</> |    55.56</> |                  </> |
- coverage-report                    </> |    41.18</> |        0</> |       25</> |    42.86</> |                  </> |
-  OtherFile.js                      </> |      100</> |      100</> |      100</> |      100</> |                  </> |
-  Sum.js                            </> |    85.71</> |      100</> |       50</> |      100</> |                  </> |
-  SumDependency.js                  </> |        0</> |        0</> |        0</> |        0</> |           8,10,12</> |
-  notRequiredInTestSuite.js         </> |        0</> |        0</> |        0</> |        0</> |     8,15,16,17,19</> |
- coverage-report/cached-duplicates/a</> |      100</> |      100</> |      100</> |      100</> |                  </> |
-  Identical.js                      </> |      100</> |      100</> |      100</> |      100</> |                  </> |
- coverage-report/cached-duplicates/b</> |      100</> |      100</> |      100</> |      100</> |                  </> |
-  Identical.js                      </> |      100</> |      100</> |      100</> |      100</> |                  </> |
+All files                            |    59.09 |        0 |       50 |    58.82 |                   |
+ coverage-report                     |    43.75 |        0 |       25 |    46.15 |                   |
+  OtherFile.js                       |      100 |      100 |      100 |      100 |                   |
+  Sum.js                             |    85.71 |      100 |       50 |      100 |                   |
+  SumDependency.js                   |        0 |        0 |        0 |        0 |           8,10,12 |
+  notRequiredInTestSuite.js          |        0 |        0 |        0 |        0 |       15,16,17,19 |
+ coverage-report/cached-duplicates/a |      100 |      100 |      100 |      100 |                   |
+  Identical.js                       |      100 |      100 |      100 |      100 |                   |
+ coverage-report/cached-duplicates/b |      100 |      100 |      100 |      100 |                   |
+  Identical.js                       |      100 |      100 |      100 |      100 |                   |
 -------------------------------------|----------|----------|----------|----------|-------------------|"
 `;
 
@@ -72,12 +72,12 @@ exports[`outputs coverage report 1`] = `
 "-------------------------------------|----------|----------|----------|----------|-------------------|
 File                                 |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
 -------------------------------------|----------|----------|----------|----------|-------------------|
-All files                            |    56.52 |        0 |       50 |    55.56 |                   |
- coverage-report                     |    41.18 |        0 |       25 |    42.86 |                   |
+All files                            |    59.09 |        0 |       50 |    58.82 |                   |
+ coverage-report                     |    43.75 |        0 |       25 |    46.15 |                   |
   OtherFile.js                       |      100 |      100 |      100 |      100 |                   |
   Sum.js                             |    85.71 |      100 |       50 |      100 |                   |
   SumDependency.js                   |        0 |        0 |        0 |        0 |           8,10,12 |
-  notRequiredInTestSuite.js          |        0 |        0 |        0 |        0 |     8,15,16,17,19 |
+  notRequiredInTestSuite.js          |        0 |        0 |        0 |        0 |       15,16,17,19 |
  coverage-report/cached-duplicates/a |      100 |      100 |      100 |      100 |                   |
   Identical.js                       |      100 |      100 |      100 |      100 |                   |
  coverage-report/cached-duplicates/b |      100 |      100 |      100 |      100 |                   |
@@ -88,20 +88,20 @@ All files                            |    56.52 |        0 |       50 |    55.56
 exports[`outputs coverage report when text and text-summary is requested 1`] = `
 "
 =============================== Coverage summary ===============================
-Statements   : 56.52% ( 13/23 )
+Statements   : 59.09% ( 13/22 )
 Branches     : 0% ( 0/4 )
 Functions    : 50% ( 3/6 )
-Lines        : 55.56% ( 10/18 )
+Lines        : 58.82% ( 10/17 )
 ================================================================================
 -------------------------------------|----------|----------|----------|----------|-------------------|
 File                                 |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
 -------------------------------------|----------|----------|----------|----------|-------------------|
-All files                            |    56.52 |        0 |       50 |    55.56 |                   |
- coverage-report                     |    41.18 |        0 |       25 |    42.86 |                   |
+All files                            |    59.09 |        0 |       50 |    58.82 |                   |
+ coverage-report                     |    43.75 |        0 |       25 |    46.15 |                   |
   OtherFile.js                       |      100 |      100 |      100 |      100 |                   |
   Sum.js                             |    85.71 |      100 |       50 |      100 |                   |
   SumDependency.js                   |        0 |        0 |        0 |        0 |           8,10,12 |
-  notRequiredInTestSuite.js          |        0 |        0 |        0 |        0 |     8,15,16,17,19 |
+  notRequiredInTestSuite.js          |        0 |        0 |        0 |        0 |       15,16,17,19 |
  coverage-report/cached-duplicates/a |      100 |      100 |      100 |      100 |                   |
   Identical.js                       |      100 |      100 |      100 |      100 |                   |
  coverage-report/cached-duplicates/b |      100 |      100 |      100 |      100 |                   |
@@ -113,12 +113,12 @@ exports[`outputs coverage report when text is requested 1`] = `
 "-------------------------------------|----------|----------|----------|----------|-------------------|
 File                                 |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
 -------------------------------------|----------|----------|----------|----------|-------------------|
-All files                            |    56.52 |        0 |       50 |    55.56 |                   |
- coverage-report                     |    41.18 |        0 |       25 |    42.86 |                   |
+All files                            |    59.09 |        0 |       50 |    58.82 |                   |
+ coverage-report                     |    43.75 |        0 |       25 |    46.15 |                   |
   OtherFile.js                       |      100 |      100 |      100 |      100 |                   |
   Sum.js                             |    85.71 |      100 |       50 |      100 |                   |
   SumDependency.js                   |        0 |        0 |        0 |        0 |           8,10,12 |
-  notRequiredInTestSuite.js          |        0 |        0 |        0 |        0 |     8,15,16,17,19 |
+  notRequiredInTestSuite.js          |        0 |        0 |        0 |        0 |       15,16,17,19 |
  coverage-report/cached-duplicates/a |      100 |      100 |      100 |      100 |                   |
   Identical.js                       |      100 |      100 |      100 |      100 |                   |
  coverage-report/cached-duplicates/b |      100 |      100 |      100 |      100 |                   |
@@ -129,9 +129,9 @@ All files                            |    56.52 |        0 |       50 |    55.56
 exports[`outputs coverage report when text-summary is requested 1`] = `
 "
 =============================== Coverage summary ===============================
-Statements   : 56.52% ( 13/23 )
+Statements   : 59.09% ( 13/22 )
 Branches     : 0% ( 0/4 )
 Functions    : 50% ( 3/6 )
-Lines        : 55.56% ( 10/18 )
+Lines        : 58.82% ( 10/17 )
 ================================================================================"
 `;