Added the done() callback to make the spec asynchronous. (from Jeff Dickley's "Trust, Tools, and Tripping Over Shoelaces While Dancing" blog post - http://archlever.blogspot.com/2013/11/trust-tools-and-tripping-over-shoelaces.html)

gateway_spec.coffee

#= require 'gateway'

describe 'Gateway class', ->
  
  beforeEach (done) ->
    @subject = new window.meldd.Gateway()
    @name = 'foo'
    @value = $('body')
    done()

  # other specs elided...

  describe 'has a "useGroup" method that', ->
    
    it 'takes one parameter', (done) ->
      expect(@subject.useGroup).to.have.length 1
      done()

    describe 'when called using', ->
      
      it 'a nonexistent group name, returns an empty object hash', (done) ->
        group = @subject.useGroup 'not found'
        expect(group).to.be.an 'object'
        expect(group).to.be.empty()
        done()

      describe 'a group with one key, returns an object', ->
        
        beforeEach (done) ->
          @subject.register 'foo', 'bar', 'group1'
          @group = @subject.useGroup 'group1'
          done()

        it 'hash', (done) ->
          expect(@group).to.be.an 'object'
          done()

        it 'with the correct single item name as the only key', (done) ->
          expect(@subject.groups['group1'][0]).to == 'bar'
          expect(Object.keys(@group)).to == ['foo']
          done()

        it 'with the correct item value as the only value', (done) ->
          expect(@group['foo']).to == 'bar'
          done()

      describe 'two groups with one identical key, returns', ->
        
        beforeEach (done) ->
          @subject.register 'this', @, 'group1', 'group2'
          @group1 = @subject.useGroup 'group1'
          @group2 = @subject.useGroup 'group2'
          done()

        it 'the identical object in both groups', (done) ->
          # equality to avoid "Converting circular structure to JSON" error
          expect(@group1['this']).to == @
          expect(@group2['this']).to == @
          # identity; they're the exact same object instance
          expect(@group1['this']).to.be @group2['this']
          done()