test_fixture_factory.coffee

# `factory` implements test fixtures as object factories. 
factory = (fixture) ->
  defaults = if _.isFunction(fixture) then fixture() else fixture
  (klass, attrs) ->
    if _.isFunction(klass) # build it
      new klass(_.extend {}, defaults, attrs)
    elseif _.isObject(klass) # no klass, just attrs
      _.extend {}, defaults, klass
    else # 
      defaults

usage.md

Using the factory

Given a fixture defined like so:

FooFixture = factory ->
  id: 13
  foo: 'bar'

the factory may be used to retrieve the raw fixture:

attributes = FooFixture()
model = new MyModel(attributes)

or to pass the fixture as a constructor argument:

model = new FooFixture(MyModel) # equivalent to above

Overriding the fixture

attributes = FooFixture(id: 42)
model = new MyModel(attributes)    

model = new FooFixture(MyModel, id: 42) # override ID