'L{plugin.getPlugins} should return the list of plugins matching the
specified interface (here, L{ITestPlugin2}), and these plugins
should be instances of classes with a C{test} method, to be sure
L{plugin.getPlugins} load classes correctly.'

def test_plugins(self):

    plugins = list(plugin.getPlugins(ITestPlugin2, self.module))
    self.assertEqual(len(plugins), 2)
    names = ['AnotherTestPlugin', 'ThirdTestPlugin']
    for p in plugins:
        names.remove(p.__name__)
        p.test()
