Undefined is not a function is CoffeeScript / Angular / Jasmine

I've written a short unit test based on the example from the Angular unit-testing documentation. I've tried to create a jsfiddle with no luck, so please bear with me.

# app definition
app = module 'myApp', []
.controller 'myCtrl', ['$scope', ($scope) ->$scope.foo = 'foo']

# test
describe 'myCtrl tests', () ->
  beforeEach module 'myApp'
  $controller = undefined

  beforeEach inject (_$controller_) ->
    $controller = _$controller_

  describe 'TestEditCtrl', () ->
    it 'should not throw an error', () ->
      $scope = {}
      controller = $controller 'myCtrl',{$scope: $scope}
      expect ($scope.foo).toEqual 'foo'

When I run this test, I get "TypeError: undefined is not a function" for $scope.foo and the test fails.