new_contents: #!/usr/bin/env python
  
  import pytest
  
  from circuits import handler, Component, Event
  
  
  class wait(Event):
      """wait Event"""
  
      success = True
  
  
  class hello(Event):
      """hello Event"""
  
      success = True
  
  
  class App(Component):
  
      @handler("wait")
      def _on_wait(self):
          e = hello()
          x = self.fire(e)
          yield self.wait(e)
          yield x.value
  
      def hello(self):
          return "Hello World!"
  
  
  @pytest.fixture
  def app(request, manager, watcher):
      app = App().register(manager)
      assert watcher.wait("registered")
  
      def finalizer():
          app.unregister()
  
      request.addfinalizer(finalizer)
  
      return app
  
  
  def test_wait_instance(manager, watcher, app):
      x = manager.fire(wait())
      assert watcher.wait("wait_success")
  
      value = x.value
      assert value == "Hello World!"
  
subject: Add unit test for waiting for event instances (Closes #60)