describe is a simple BDD framework for Javascript.

Example:

describe('remove()')
    .before(function(){
        this.array = ['a', 'b', 'c'];
    })
    .should('remove single elements', function(){
        remove(this.array, 0)
        expect(this.array.length).toBe(2);
        expect(this.array).toEqual(['b', 'c'])
    })
    .should('remove multiple elements', function(){
        remove(this.array, 0, 2)
        expect(this.array.length).toBe(1)
        expect(this.array).toEqual(['c'])
    })

Example Passing Output:

Ran 2 specs for remove().
0 failures.

Example Failing output:

remove() should remove single elements:
    Error: 3 is not the same object as 2
        at Object.toBe (file://localhost/Users/airportyh/Projects/github/describe/describe.js:218:21)
        at Object.testFunc (file://localhost/Users/airportyh/Projects/github/describe/examples/example.html:16:35)
remove() should remove multiple elements:
    Error: 3 is not the same object as 1
        at Object.toBe (file://localhost/Users/airportyh/Projects/github/describe/describe.js:218:21)
        at Object.testFunc (file://localhost/Users/airportyh/Projects/github/describe/examples/example.html:21:35)
Ran 2 specs for remove().
2 failures.

Async Example:

describe('Simple Async Test')
    .should('be able to finish test after timeout', {async: true}, function(){
        var self = this
		var val = 1
        setTimeout(function(){
			self.expect(val).toBe(1)
            self.finish()
        }, 300)
    })

To Run the Specs:

To run all specs described, call describe.run(). Describe outputs the results of the tests in plain text when run. To output to a DOM element by ID - if you are running in a web browser:

describe.run({printTo: 'log'})

"log" is the ID of the element in the example.

If you are running in other Javascript environments such as node.js or narwhal, specify the print function that describe should use for output (it should take one string argument):

describe.run({print: require('sys').puts})

The above example would work for node.js.

The describe function

The describe function starts the definition of a spec. Its return value is a Spec object, which you'd add individual fixtures or test cases to. It's signature is:

describe(name, options)

Options

These options apply to all test cases within this spec, but may be overriden in individual test cases.

• async: (true or false), whether the test cases in this spec should be run async by default.
• asyncTimeout: (number in milliseconds), applicable only for async tests, the max time to wait for a test to complete. If it does not complete within the specified time, it will fail with the "Timed out" error message. The default value is 1000, or 1 second. If you provide this option, describe assumes async to be true.

Spec Object methods

should(description, options, function)

Adds a test case to the spec. It optionally takes the same options as the describe function - but if you don't provide any options, you can just leave them out(no need to provide a null or {}).

it(description, options, function)

Adds a test case to the spec. It optionally takes the same options as the describe function - but if you don't provide any options, you can just leave them out(no need to provide a null or {}).

before(function)

Adds a setup function that executes before each test case in this spec.

beforeAll(function)

Adds a setup function that executes once before all test cases are run.

after(function)

Adds a tear-down function that executes after each test case in this spec.

afterAll(function)

Adds a tear-down function that executes after all test cases in this spec have finished.

Test Object methods

A Test object represents an individual test case within a spec, and is also the context within which your test functions run(the this variable). These methods are available to you on the Test object.

expect(one).toBe(other)

Okay, I lied, this is actually a combination of 2 method calls, but this way is easier to document, I think. The expect(one).toBe(other) asserts that one is === other.

expect(one).toEqual(other)

Asserts that one is equal to other. The definition of equal to is as follows:

1. if one and other are of different types, they are not equal
2. if one and other are Dates, they are equal when one.getTime() == other.getTime()
3. if one and other are Arrays, they are equal when they have the same length and for all i, one[i] == other[i]
4. if one and other are simple object literals, they are equal when they have the same JSON representation
5. otherwise, one and other are equal when one == other

expect(function).toRaise(errorMessage)

Asserts that a function, when executed will throw an error, optionally with a specified error message.

fail(errorMessage)

Fails this test case immediately, optionally with a specified error message.

finish()

Applicable only to async test cases: finishes the test case immediately.

License

(The MIT License)

Copyright (c) 2010, Toby Ho

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.