def test_set_var(adata, subset_func):
    init_hash = joblib.hash(adata)

    subset = adata[:, subset_func(adata.var_names)]

    new_var = pd.DataFrame(
        dict(a=np.ones(subset.n_vars), b=np.ones(subset.n_vars)),
        index=subset.var_names,
    )

    assert subset.is_view
    subset.var = new_var
    assert not subset.is_view
    assert np.all(subset.var == new_var)

    assert joblib.hash(adata) == init_hash
def _reset_exiter(cls, exiter: Optional[Exiter]) -> None:
        """Class state:

        - Overwrites `cls._exiter`.
        Python state:
        - Overwrites sys.excepthook.
        """
        logger.debug(f"overriding the global exiter with {exiter} (from {cls._exiter})")
        # NB: mutate the class variables! This is done before mutating the exception hook, because the
        # uncaught exception handler uses cls._exiter to exit.
        cls._exiter = exiter
        # NB: mutate process-global state!
        sys.excepthook = cls._log_unhandled_exception_and_exit