A simple assertion library for server and client side JavaScript. Assert can be used with most test frameworks.

Browser Support: Android Browser 2.2–4.2, Firefox 3.6, Firefox 4–22, Google Chrome 14–28, Internet Explorer 6–10, Mobile Safari iOS 3–6, Safari 5–6

All assertions throw AssertionError if they fail.

Throw an assertion error.

assert.fail('foo', 'bar', 'Foo equals bar', '===');

Assert that value is truthy.

Assert that value is falsy.

Assert that actual == expected.

Assert that actual != expected.

Assert that actual === expected.

Assert that actual !== expected.

Assert that actual is deeply equal to expected.

Assert that actual is not deeply equal to expected.

Assert that fn throws an error. If expected is present then the thrown error will be tested as follows:

• If expected is a function, assert that error intanceof expected
• If expected is a string, assert that error.message === expected
• If expected is a RegExp, assert that expected.test(error) === true

Assert that fn does not throw an error. If expected is present then the assertion is that an error can be thrown, but it does not pass the tests outlined in assert.throws.

Assert that typeof actual === expected.

Assert that typeof actual !== expected.

Assert that actual instanceof expected.

Assert that !(actual instanceof expected).

Assert that value is an array.

Assert that value is not an array.

Assert that value is a boolean.

Assert that value is not a boolean.

Assert that value === true.

Assert that value === false.

Assert that value is a function.

Assert that value is not a function.

Assert that value === null.

Assert that value !== null.

Assert that value is a number.

Assert that value is not a number.

Assert that value is an object.

Assert that value is not an object.

Assert that value is a string.

Assert that value is not a string.

Assert that value === undefined.

Assert that value !== undefined.

Assert that actual matches the RegExp in expected.

Assert that actual does not match the RegExp in expected.

Assert that haystack contains needle. For strings and arrays, this asserts that indexOf returns a value other than -1. For objects, this method asserts that needle is the name of a property on haystack.

Assert that haystack does not contain needle. See assert.includes.

Assert that value.length === expected.

Assert that actual < expected.

Assert that actual <= expected.

Assert that actual > expected.

Assert that actual >= expected.

Assert is a fork of Procliam, licensed under the MIT license.