'Verify ``show_placeholder`` correctly handles being given an
invalid identifier.'

def test_show_placeholder_for_page_placeholder_does_not_exist(self):

    with self.settings(DEBUG=True):
        context = self.get_context('/')
        self.assertRaises(Placeholder.DoesNotExist, _show_placeholder_by_id, context, 'does_not_exist', 'myreverseid')
    with self.settings(DEBUG=False):
        content = _show_placeholder_by_id(context, 'does_not_exist', 'myreverseid')
        self.assertEqual(content, '')
