a unit-testing framework for javascript
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Jest: a unit-testing framework for javascript in the browser.


Jest.js simplifies javascript testing.

Getting Started

Add Jest to an HTML file:

<link href="jest.css" rel="stylesheet" type="text/css">
<script src="jest.js"></script>

Add your tests:

<script src="tests.js"></script>

Indicate where on the page the tests should appear:

<div id="jest"></div>

Create tests

Jest organizes individual tests into test-groups and test-groups into modules. Each test file should begin with the declaration of the module name:

jest('boolean module');

Each test-group following this declaration will be considered a member of module 'boolean module', unless jest() is called again with a different module name.

A test-group is declared with a name, a callback containing the tests, and the expected number of tests:

test('true tests', function () {
    yes(true, 'true is true');
    no(!true, 'not true is false');
}, 2);

For a complete demonstration of Jest's functions, see examples/tests.js or open html/jest.html in your browser.

Run tests

Loading an HTML page with the proper resources and <div id="jest"></div> in the body will run Jest.