decorators.py 文件源码

def ensure_executable_exists(name, get_executable):
    """Ensures that the private executable exists. If it doesn't, then
    call get_executable, which must be a callable that installs
    the executable.
    """
    def decorator(f):
        @click.pass_context
        def new_func(ctx, *args, **kwargs):
            """
            @type ctx: click.Context
            """
            path = path_utils.executable_path(name)
            if not os.path.exists(path):
                echo_heading('Installing {}.'.format(name), marker='-', marker_color='magenta')
                get_executable()
                assert os.path.exists(path)
            return ctx.invoke(f, *args, **kwargs)
        return update_wrapper(new_func, f)
    return decorator