pola-rs/polars · error · ValueError

unrecognised deprecation type {tp!r}.\nExpected one (or more

Error message

unrecognised deprecation type {tp!r}.\nExpected one (or more) of {repr(sorted(valid_types))[1:-1]}

What it means

Validation inside identify_deprecations: one of the strings in `types` is not a member of the DeprecationType literal ('function', 'renamed_parameter', 'nonkeyword_arguments', 'parameter_as_multi_positional', ...). The invalid type string is the faulty input.

Source

Thrown at py-polars/src/polars/_utils/deprecation.py:339

            - "function"
            - "renamed_parameter"
            - "nonkeyword_arguments"
            - "parameter_as_multi_positional"

    Examples
    --------
    >>> from polars._utils.deprecation import identify_deprecations
    >>> identify_deprecations("nonkeyword_arguments")  # doctest: +IGNORE_RESULT
    {'nonkeyword_arguments': ['functions.business.business_day_count']}
    """
    valid_types = set(get_args(DeprecationType))
    for tp in types:
        if tp not in valid_types:
            msg = (
                f"unrecognised deprecation type {tp!r}.\n"
                f"Expected one (or more) of {repr(sorted(valid_types))[1:-1]}"
            )
            raise ValueError(msg)

    package_path = Path(sys.modules["polars"].__file__).parent  # type: ignore[arg-type]
    results = defaultdict(list)

    for py_file in package_path.rglob("*.py"):
        rel_path = py_file.relative_to(package_path)
        module_path = ".".join(rel_path.parts).removesuffix(".py")
        with py_file.open("r", encoding="utf-8") as src:
            for deprecation_type, func_names in _find_deprecated_functions(
                source=src.read(),
                module_path=module_path,
            ).items():
                if deprecation_type not in valid_types:
                    # note: raising here implies we have a new deprecation function
                    # that should be added to the DeprecationType type alias
                    msg = f"unrecognised deprecation type {tp!r}.\n"
                    raise ValueError(msg)

View on GitHub (pinned to 5d8ebabf11)

Solutions

1. Use a valid deprecation type among the listed valid_types.

Example fix

deprecate(..., types=('param',))

When it happens

Trigger: Internal deprecation helper received an unknown deprecation type.

Common situations: See trigger scenarios.

AI-assisted analysis of pola-rs/polars@5d8ebabf11 (2026-08-19). Data as JSON: /api/errors/c39dc4b28cab39f0. Report an issue: GitHub.