def setUp(self):
        self._directory = tempfile.mkdtemp(dir='.')
        self._proto_path = path.join(self._directory, _RELATIVE_PROTO_PATH)
        self._python_out = path.join(self._directory, _RELATIVE_PYTHON_OUT)

        os.makedirs(self._proto_path)
        os.makedirs(self._python_out)

        directories_path_components = {
            proto_file_path_components[:-1]
            for proto_file_path_components in _PROTO_FILES_PATH_COMPONENTS
        }
        _create_directory_tree(self._proto_path, directories_path_components)
        self._proto_file_names = set()
        for proto_file_path_components in _PROTO_FILES_PATH_COMPONENTS:
            raw_proto_content = pkgutil.get_data(
                'tests.protoc_plugin.protos',
                path.join(*proto_file_path_components[1:]))
            massaged_proto_content = _massage_proto_content(raw_proto_content)
            proto_file_name = path.join(self._proto_path,
                                        *proto_file_path_components)
            with open(proto_file_name, 'wb') as proto_file:
                proto_file.write(massaged_proto_content)
            self._proto_file_names.add(proto_file_name)