def extract_bower_zipfile(self, zip_file, dest, expected_version=None):
        bower_json = None
        root = None
        deps_installed = []
        for info in zip_file.infolist():
            if PurePath(info.filename).name == "bower.json":
                with zip_file.open(info) as f:
                    bower_json = json.load(f)
                    root = str(PurePath(info.filename).parent)
                break
        version = bower_json["version"]
        if expected_version is not None:
            expected_version = Bower.clean_semver(expected_version)
            if not semver.match(version, expected_version):
                click.secho("error: versions do not match ({} =/= {})".format(
                    version, expected_version))
                raise InvalidPackageError
        if "dependencies" in bower_json:
            for package, version in bower_json["dependencies"].items():
                url = Bower.get_package_url(package)
                deps_installed.extend(self.get_bower_package(
                    url, dest=dest, version=version))
        ignore_patterns = [GitIgnorePattern(ig) for ig in bower_json["ignore"]]
        path_spec = PathSpec(ignore_patterns)
        namelist = [path for path in zip_file.namelist()
                    if PurePath(path).parts[0] == root]
        ignored = list(path_spec.match_files(namelist))
        for path in namelist:
            dest_path = PurePath(
                bower_json["name"],
                *PurePath(path).parts[1:])

            if path in ignored:
                continue

            for path in ignored:
                for parent in PurePath(path):
                    if parent in ignored:
                        continue

            if path.endswith("/"):
                if list(path_spec.match_files([str(dest_path)])):
                    ignored.append(PurePath(path))
                elif not (dest / dest_path).is_dir():
                    (dest / dest_path).mkdir(parents=True)
            else:
                target_path = dest / dest_path.parent / dest_path.name
                source = zip_file.open(path)
                target = target_path.open("wb")
                with source, target:
                    shutil.copyfileobj(source, target)
        deps_installed.append((bower_json["name"], bower_json["version"]))
        return deps_installed
def always(self):
        return self._always