jest-browser-globals

Lets you run Jest in a browser. Works with Mocha, which is expected to be in the global scope first.

Makes the following available:

expect
jest.fn - mock functions
test.each - one of the few globals that Mocha doesn't define

Installation

Run npm install --save-dev jest-browser-globals

In a test runner like Karma, include the built file in the global scope:

// karma.config.js
 
module.exports = {
  frameworks: [ 'mocha' ],
  files: [
    './node_modules/jest-browser-globals/build-es5/index.js'
    // other test files...
  ]
}

To run it in an HTML file, do something like this:

<!DOCTYPE html>
<html>
  <head>
    <meta charset='utf-8' />
    <link href='https://cdn.jsdelivr.net/npm/mocha@7.0.1/mocha.css' rel='stylesheet' />
    <script src='https://cdn.jsdelivr.net/npm/mocha@7.0.1/mocha.js'></script> 
    <script>mocha.setup('bdd')</script> 
    <script src='./node_modules/jest-browser-globals/build-es5/index.js'></script> 
    <script>
 
      describe('cool thing', function() {
        test('that is works', function() {
          expect(5).toBe(6);
        });
      });
 
    </script> 
  </head>
  <body>
    <div id='mocha'></div>
    <script>mocha.run()</script> 
  </body>
</html>

Fork Info

This package has been created from a fork of the Jest Project. It aggregates the expect, jest-mock, and jest-each packages, attaches them to the window, and does various other things to ensure that Jest runs similarly to how it runs in Node. It also strips out lots of dependencies that only make sense in a Node environment, resulting in a slimmer build.

jest-browser-globals

jest-browser-globals

Installation

Fork Info