'Enable a plugin with cyclic dependencies.'

def test_enable_cyclic_dependencies(self):

    p = PluginManager(None)
    events = []
    B.plugin_init = (lambda s: events.append('init_b'))
    C.plugin_init = (lambda s: events.append('init_c'))
    D.plugin_init = (lambda s: events.append('init_d'))
    p.enable('c')
    self.assertEqual(len(p), 3, 'Wrong    number    of    enabled    plugins.')
    self.assertTrue(('init_b' in events), 'Dependency    B    not    enabled.')
    self.assertTrue(('init_c' in events), 'Dependency    C    not    enabled.')
    self.assertTrue(('init_d' in events), 'Dependency    D    not    enabled.')
