docs: setting up babel, fixes regeneratorRuntime not defined

CHANGELOG.md

@@ -171,6 +171,7 @@
 - `[diff-sequences]` Add performance benchmark to package ([#7603](https://github.com/facebook/jest/pull/7603))
 - `[*]` Replace as many `Object.assign` with object spread as possible ([#7627](https://github.com/facebook/jest/pull/7627))
 - `[ci]` Initial support for Azure Pipelines ([#7556](https://github.com/facebook/jest/pull/7556))
+- `[docs]` Changed Babel setup documentation to fix `async/await` ([#7701](https://github.com/facebook/jest/pull/7701))
 
 ### Performance
 

docs/GettingStarted.md

@@ -81,21 +81,35 @@ jest --init
 
 ### Using Babel
 
-To use [Babel](http://babeljs.io/), install the `babel-jest` and `@babel/core` packages via `yarn`:
+To use [Babel](http://babeljs.io/), install required development dependencies via `yarn`:
 
 ```bash
-yarn add --dev babel-jest @babel/core
+yarn add --dev @babel/core @babel/preset-env @babel/preset-react
 ```
 
-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 ES2018 and [React](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:
+Install `@babel/polyfill`:
 
-```js
-module.exports = {
- presets: ['@babel/preset-env', '@babel/preset-react'],
-};
+```bash
+yarn add @babel/polyfill
 ```
 
-You are now set up to use all ES2018 features and React-specific syntax.
+Load the polyfill and configure Babel in your `package.json` file:
+
+```json
+// package.json
+{
+ "jest": {
+ "setupFiles": ["@babel/polyfill"]
+ },
+ "babel": {
+ "presets": ["@babel/preset-env", "@babel/preset-react"]
+ }
+}
+```
+
+You should also import `@babel/polyfill` in your app. If you are creating a library you should look into using [`@babel/plugin-transform-runtime`](https://babeljs.io/docs/en/babel-plugin-transform-runtime) instead.
+
+You are now set up to use all ES2018 features and [React](https://reactjs.org) specific syntax. If you are not using React you can exclude `@babel/preset-react` from the above commands/config.
 
 > 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: