Initial pass

node_modules/jest-circus/README.md

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+<h1 align="center">
+  <img src="https://jestjs.io/img/jest.png" height="150" width="150"/>
+  <img src="https://jestjs.io/img/circus.png" height="150" width="150"/>
+  <p align="center">jest-circus</p>
+  <p align="center">The next-gen test runner for Jest</p>
+</h1>
+
+## Overview
+
+Circus is a flux-based test runner for Jest that is fast, easy to maintain, and simple to extend.
+
+Circus allows you to bind to events via an optional event handler on any [custom environment](https://jestjs.io/docs/en/configuration#testenvironment-string). See the [type definitions](https://github.com/facebook/jest/blob/master/packages/jest-circus/src/types.ts) for more information on the events and state data currently available.
+
+```js
+import {NodeEnvironment} from 'jest-environment-node';
+import {Event, State} from 'jest-circus';
+
+class MyCustomEnvironment extends NodeEnvironment {
+  //...
+
+  handleTestEvent(event: Event, state: State) {
+    if (event.name === 'test_start') {
+      // ...
+    }
+  }
+}
+```
+
+Mutating event or state data is currently unsupported and may cause unexpected behavior or break in a future release without warning. New events, event data, and/or state data will not be considered a breaking change and may be added in any minor release.
+
+## Installation
+
+Install `jest-circus` using yarn:
+
+```bash
+yarn add --dev jest-circus
+```
+
+Or via npm:
+
+```bash
+npm install --save-dev jest-circus
+```
+
+## Configure
+
+Configure Jest to use `jest-circus` via the [`testRunner`](https://jestjs.io/docs/en/configuration#testrunner-string) option:
+
+```json
+{
+  "testRunner": "jest-circus/runner"
+}
+```
+
+Or via CLI:
+
+```bash
+jest --testRunner='jest-circus/runner'
+```