def test_not_set_subset_X(matrix_type, subset_func):
    adata = ad.AnnData(matrix_type(asarray(sparse.random(20, 20))))
    init_hash = joblib.hash(adata)
    orig_X_val = adata.X.copy()
    while True:
        subset_idx = slice_subset(adata.obs_names)
        if len(adata[subset_idx, :]) > 2:
            break
    subset = adata[subset_idx, :]

    subset = adata[:, subset_idx]

    internal_idx = _normalize_index(
        subset_func(np.arange(subset.X.shape[1])), subset.var_names
    )
    assert subset.is_view
    subset.X[:, internal_idx] = 1
    assert not subset.is_view
    assert not np.any(asarray(adata.X != orig_X_val))

    assert init_hash == joblib.hash(adata)
def log_exception(cls, msg):
        """Try to log an error message to this process's error log and the shared error log.

        NB: Doesn't raise (logs an error instead).
        """
        pid = os.getpid()
        fatal_error_log_entry = cls._format_exception_message(msg, pid)

        # We care more about this log than the shared log, so write to it first.
        try:
            cls._try_write_with_flush(cls._pid_specific_error_fileobj, fatal_error_log_entry)
        except Exception as e:
            logger.error(
                "Error logging the message '{}' to the pid-specific file handle for {} at pid {}:\n{}".format(
                    msg, cls._log_dir, pid, e
                )
            )

        # Write to the shared log.
        try:
            # TODO: we should probably guard this against concurrent modification by other pants
            # subprocesses somehow.
            cls._try_write_with_flush(cls._shared_error_fileobj, fatal_error_log_entry)
        except Exception as e:
            logger.error(
                "Error logging the message '{}' to the shared file handle for {} at pid {}:\n{}".format(
                    msg, cls._log_dir, pid, e
                )
            )