def test_extensions_loading(self):
markup = MarkdownMarkup()
self.assertIsNone(markup._canonicalize_extension_name('nonexistent'))
self.assertIsNone(markup._canonicalize_extension_name('nonexistent(someoption)'))
self.assertIsNone(markup._canonicalize_extension_name('.foobar'))
self.assertEqual(markup._canonicalize_extension_name('meta'), 'markdown.extensions.meta')
name, parameters = markup._split_extension_config('toc(anchorlink=1, foo=bar)')
self.assertEqual(name, 'toc')
self.assertEqual(parameters, {'anchorlink': '1', 'foo': 'bar'})
