Update README.md

README.md

@@ -5,22 +5,30 @@
 
 🃏 Delightful JavaScript Testing
 
-- **👩🏻‍💻 Easy Setup**: Jest is a complete and easy to set up JavaScript testing solution. In fact, Jest works out of the box for any React project.
+- **👩🏻‍💻 Easy Setup**: Complete and easy to set-up JavaScript testing solution. Works out of the box for any React project.
 
-- **🏃🏽 Instant Feedback**: Failed tests run first. Fast interactive mode can switch between running all tests or only test files related to changed files.
+- **🏃🏽 Instant Feedback**: Fast interactive watch mode runs only test files related to changed files and is optimized to give signal quickly.
 
-- **📸 Snapshot Testing**: Jest can [capture snapshots](http://facebook.github.io/jest/docs/en/snapshot-testing.html) of React trees or other serializable values to simplify testing.
+- **📸 Snapshot Testing**: Capture snapshots of React trees or other serializable values to simplify testing and to analyze how state changes over time.
 
 ## Getting Started
 
 <!-- generated_getting_started_start -->
-Install Jest using `npm`:
+
+Install Jest using [`npm`](https://www.npmjs.com/):
 
 ```
 npm install --save-dev jest
 ```
 
-Let's get started by writing a test for a hypothetical function that adds two numbers. First, create a `sum.js` file:
+Or via [`yarn`](https://yarnpkg.com/en/package/jest):
+
+```
+yarn add --dev jest
+```
+
+Let's get started by writing a test for a hypothetical function that adds two
+numbers. First, create a `sum.js` file:
 
 ```javascript
 function sum(a, b) {
@@ -58,33 +66,51 @@ PASS  ./sum.test.js
 
 **You just successfully wrote your first test using Jest!**
 
-This test used `expect` and `toBe` to test that two values were exactly identical. To learn about the other things that Jest can test, see [Using Matchers](https://facebook.github.io/jest/docs/en/using-matchers.html).
+This test used `expect` and `toBe` to test that two values were exactly
+identical. To learn about the other things that Jest can test, see
+[Using Matchers](UsingMatchers.md).
 
 ## Running from command line
 
-You can run Jest directly from the CLI (if it's globally available in your `PATH`, e.g. by `npm install -g jest`) with variety of useful options.
+You can run Jest directly from the CLI (if it's globally available in your
+`PATH`, e.g. by `npm install -g jest`) with variety of useful options.
 
-Here's how to run Jest on files matching `my-test`, using `config.json` as a configuration file and display a native OS notification after the run:
+Here's how to run Jest on files matching `my-test`, using `config.json` as a
+configuration file and display a native OS notification after the run:
 
 ```bash
 jest my-test --notify --config=config.json
 ```
 
-If you'd like to learn more about running `jest` through the command line, take a look at the [Jest CLI Options](https://facebook.github.io/jest/docs/en/cli.html) page.
+If you'd like to learn more about running `jest` through the command line, take
+a look at the [Jest CLI Options](CLI.md) page.
 
 ## Additional Configuration
 
 ### Using Babel
 
-To use [Babel](http://babeljs.io/), install the `babel-jest` and `regenerator-runtime` packages:
+To use [Babel](http://babeljs.io/), install the `babel-jest` and
+`regenerator-runtime` packages:
 
 ```
-npm install --save-dev jest babel-jest regenerator-runtime
+npm install --save-dev babel-jest babel-core regenerator-runtime
 ```
 
-*Note: Explicitly installing `regenerator-runtime` is not needed if you use `npm` 3 or 4 or Yarn*
+> Note: If you are using a babel version 7 then you need to install `babel-jest`
+> with the following command:
+>
+> ```
+> npm install --save-dev babel-jest 'babel-core@^7.0.0-0' @babel/core regenerator-runtime
+> ```
+
+_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-es2015`](https://babeljs.io/docs/plugins/preset-es2015/) and [`babel-preset-react`](https://babeljs.io/docs/plugins/preset-react/) presets:
+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-es2015`](https://babeljs.io/docs/plugins/preset-es2015/) and
+[`babel-preset-react`](https://babeljs.io/docs/plugins/preset-react/) presets:
 
 ```json
 {
@@ -94,11 +120,30 @@ Don't forget to add a [`.babelrc`](https://babeljs.io/docs/usage/babelrc/) file
 
 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 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 ES2015 modules with the option
+> `{ "modules": false }`, you have to make sure to turn this on in your test
+> environment.
+
+```json
+{
+  "presets": [["es2015", {"modules": false}], "react"],
+  "env": {
+    "test": {
+      "presets": [["es2015"], "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:
+> 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
 // package.json
@@ -111,36 +156,15 @@ It will not use `development` section like Babel does by default when no `NODE_E
 
 ### Using webpack
 
-Jest can be used in projects that use [webpack](https://webpack.github.io/) to manage assets, styles, and compilation. webpack does offer some unique challenges over other tools. Refer to the [webpack guide](https://facebook.github.io/jest/docs/en/webpack.html) to get started.
+Jest can be used in projects that use [webpack](https://webpack.github.io/) to
+manage assets, styles, and compilation. webpack does offer some unique
+challenges over other tools. Refer to the [webpack guide](Webpack.md) to get
+started.
 
 ### Using TypeScript
 
-To use TypeScript in your tests, install the `ts-jest` package and the types for Jest.
-
-```
-npm install --save-dev jest ts-jest @types/jest
-```
-
-then modify your `package.json` so the `jest` section looks something like:
-
-```json
-{
-  "jest": {
-    "transform": {
-      "^.+\\.tsx?$": "ts-jest"
-    },
-    "testRegex": "(/__tests__/.*|(\\.|/)(test|spec))\\.(jsx?|tsx?)$",
-    "moduleFileExtensions": [
-      "ts",
-      "tsx",
-      "js",
-      "jsx",
-      "json",
-      "node"
-    ]
-  }
-}
-```
+To use TypeScript in your tests you can use
+[ts-jest](https://github.com/kulshekhar/ts-jest).
 <!-- generated_getting_started_end -->
 
 ## Documentation