def with_bundler(self):
        """
        Check, if bundler check is requested.

        Check, if the user wants us to check for new gems and return True in
        this case.
        :rtype : bool
        """

        def gemfile_exists():
            """
            Check, if a Gemfile exists in the current repo.
            """
            return os.path.exists('Gemfile')

        if 'GIT_UP_BUNDLER_CHECK' in os.environ:
            print(colored(
                '''The GIT_UP_BUNDLER_CHECK environment variable is deprecated.
You can now tell git-up to check (or not check) for missing
gems on a per-project basis using git's config system. To
set it globally, run this command anywhere:

git config --global git-up.bundler.check true

To set it within a project, run this command inside that
project's directory:

git config git-up.bundler.check true

Replace 'true' with 'false' to disable checking.''', 'yellow'))

        if self.settings['bundler.check']:
            return gemfile_exists()

        if ('GIT_UP_BUNDLER_CHECK' in os.environ
                and os.environ['GIT_UP_BUNDLER_CHECK'] == 'true'):
            return gemfile_exists()

        return False
Check, if bundler check is requested.

        Check, if the user wants us to check for new gems and return True in
        this case.
        :rtype : bool