Comment Driven Development
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.

Build Status



SpeckJS is an npm module that parses JavaScript and outputs unit-tests. SpeckJS currently supports Tape, Jasmine, and Mocha/Chai.

SpeckJS comes with plugins for Grunt, Gulp and Atom.

Our goal with SpeckJS is to make it as easy as possible to get started using Test-Driven Development on a new project, to quickly add unit-tests to your existing project, or anywhere in between. We know the value of well-tested code, and SpeckJS is here to make that simpler than ever.

How to Use


$ npm install speckjs

Creating a SpeckJS Comment

The first line of a SpeckJS comment is the title, describing your test block.

// test > sum function

Next, use SpeckJS' domain-specific language (DSL) to create an assertion of what you wish to test. Here's the format of the DSL:

// # <actual> <assertion-type> <expected> (<description>)

You can add as many (or as few) assertions as you'd like.

// # sum(1, 2) == 3 (returns the sum of both params)
// # sum(3, 4) == 7 (returns the sum of both params)

That's it! Here's a complete SpeckJS comment for the simple sum function:

// test > sum function
// # sum(1, 2) == 3 (returns the sum of both params)
// # sum(3, 4) == 7 (returns the sum of both params)

Comments can also be written using block style comments:

test > sum function
# sum(1, 2) == 3 (returns the sum of both params)
# sum(3, 4) == 7 (returns the sum of both params)

Supported Assertion Types

These are the assertion types currently supported, and you can extend this list to include others in parsing/comment-conversion.js.

==   : equal
===  : deep equal
!==  : not equal
!=== : not deep equal

Using the API

Require the module:

var speck = require('speckjs');

The API is comprised of a single function, build(file, options):

  • file (Object, required)
    • name (String)
    • content (String)
  • options (Object, optional)
    • testFW (String)
    • onBuild (Function)

By default, build returns a file (String) of all the unit-tests as indicated from the SpeckJS comments in the original file that was loaded. Here are a few examples of how you can use build:

// file object to be passed as an argument
var file = {
  name: 'demo.js',
  content: scriptContent

// options hash selecting Jasmine as testing framework over default Tape
var option1 = {
  testFW: 'jasmine'

// options hash selecting Jasmine and specifying a callback
var option2 = {
  testFW: 'jasmine',
  onBuild: function(data) {

// Returns Tape test file
var result0 =;

// Returns Jasmine test file
var result1 =, option1);

// Runs callback with new Jasmine test file, option2);


SpeckJS is also available as a plugin for the following platforms: