Object factory to create dynamic test fixtures

Usage no npm install needed!

<script type="module">
  import jsFactories from 'https://cdn.skypack.dev/js-factories';



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js-factories is a library to use dynamic fixtures using Factories in javascript/coffeescript. Ideal to combine using Mocha/chai frameworks and test rich classes for MV** Frameworks like Backbone.js


Include js-factories.js in your test suite.

Factory support is added to quickly be able to build models or other objects as you see fit:

Factory.define 'user', (attributes = {}) ->
  new User attributes

Factory.create 'user', name: 'Matthijs'
Factory.createList 10, 'user', name: 'Matthijs'


you can also use 'traits'. Traits are flags that are set when the user calls create with the factory name prefixed with terms separated by dashes.

Like: 'female-admin-user'

This will call the 'user' factory, and provide the terms 'female' and 'admin' as traits for this user

this list is accessible in the factory callback using this.traits

There are 2 helper methods to help check if traits are set:

this.trait('returns', 'one', 'of', 'these', 'values')


this.is('admin') # returns a boolean value

Extended example:

Factory.define 'user', (attributes = {}) ->
  attributes.gender = @trait('male', 'female') || 'male'

  returningClass = User
  if @is('admin')
    returningClass = AdminUser

  new returningClass attributes

Factory.create 'user', name: 'Matthijs' # => new User name: 'Matthijs'
Factory.create 'male-user', name: 'Matthijs' # => new User name: 'Matthijs', gender: 'male'
Factory.create 'male-admin-user', name: 'Matthijs' # => new AdminUser name: 'Matthijs', gender: 'male'
Factory.create 'female-user', name: 'Beppie' # => new User name: 'Beppie', gender: 'female'


Sequences are also supported:

Factory.define 'counter', ->
    amount: @sequence('amount')
    other: @sequence('other')

This does not conflict with similar names in other factory definitions.

You can also yield results:

Factory.define 'abc', ->
  @sequence (i) -> ['a','b','c'][i]

# results in:
Factory.create('abc') => 'a'
Factory.create('abc') => 'b'


You can sample a value from a list

Factory.define 'sampler', ->
  @sample 'a', 'b', 'c'

Will randomly return a, b or c every time


Copyright (c) 2012-2014 Matthijs Groen

MIT License (see the LICENSE file)