Function import_state

Lib/test/test_importlib/util.py:196–222

Context manager to manage the various importers and stored state in the sys module. The 'modules' attribute is not supported as the interpreter state stores a pointer to the dict that the interpreter uses internally; reassigning to sys.modules does not have the desired effect.

(**kwargs)

@contextlib.contextmanager
def import_state(**kwargs):
    """Context manager to manage the various importers and stored state in the
    sys module.

    The 'modules' attribute is not supported as the interpreter state stores a
    pointer to the dict that the interpreter uses internally;
    reassigning to sys.modules does not have the desired effect.

    """
    originals = {}
    try:
        for attr, default in (('meta_path', []), ('path', []),
                              ('path_hooks', []),
                              ('path_importer_cache', {})):
            originals[attr] = getattr(sys, attr)
            if attr in kwargs:
                new_value = kwargs[attr]
                del kwargs[attr]
            else:
                new_value = default
            setattr(sys, attr, new_value)
        if len(kwargs):
            raise ValueError('unrecognized arguments: {}'.format(kwargs))
        yield
    finally:
        for attr, value in originals.items():
            setattr(sys, attr, value)


class _ImporterMock: