jasmine-async.coffee

jasmine-async.coffee

  @asyncIt = (desc, test) ->

    spec = jasmine.getEnv().it desc
    __spy = new sinon.spy
    __done = no
    _NATIVE_ERR = window.onerror

    spec.runs ->
      
      # any async test must call this function in order to pass. This function is
      # passed in as the first argument to the spec that gets run.
      complete = (failed) ->

        # restore the error handler to allow for the chrome console to catch the
        # errors once everyone has been restored.
        window.onerror = _NATIVE_ERR
        
        __done = yes
        if failed is undefined
          __spy()
        else
          # continue bubbling the error to the error console
          throw failed

      # Fail specs when async internals fail.
      window.onerror = (e, _, line) ->
        er = new Error "#{e}" 
        er.stack = "Trace Unavailable, Check console for detailed message. (use @asyncBlock for async callbacks in tests)" 
        spec.fail er
        complete e
    
      # latch an async block function that will allow for better error reporting 
      # within tests themselves, as well as failing quickly when things go wrong
      # by calling out to complete()
      spec.asyncBlock = (f) ->
        ->
          try
            f.apply spec, arguments
          catch e
            spec.fail e
            complete e

      # start off the test suite, reduce test boilerplate by kicking off the
      # session loading before the test starts, and wrapping the insides in a
      # spec failer and reporter.
      try
        test.apply spec, [ complete, __app ]
      catch e
        spec.fail e
        complete e 
        
      # wait for done to be set to `yes` (happens when complete() is called.
      waitsFor -> __done

      # finally, make sure the test ended up calling the complete() function. It
      # times out after ~5 sec if none of the other error handling catches a
      # problem with the test.
      runs ->
        (expect __spy).toHaveBeenCalled "Async Complete() never called."