Class FuzzyEnum

traitlets/traitlets.py:3310–3357

An case-ignoring enum matching choices by unique prefixes/substrings.

class FuzzyEnum(Enum[G]):
    """An case-ignoring enum matching choices by unique prefixes/substrings."""

    case_sensitive = False
    #: If True, choices match anywhere in the string, otherwise match prefixes.
    substring_matching = False

    def __init__(
        self: FuzzyEnum[t.Any],
        values: t.Any,
        default_value: t.Any = Undefined,
        case_sensitive: bool = False,
        substring_matching: bool = False,
        **kwargs: t.Any,
    ) -> None:
        self.case_sensitive = case_sensitive
        self.substring_matching = substring_matching
        super().__init__(values, default_value=default_value, **kwargs)

    def validate(self, obj: t.Any, value: t.Any) -> G:
        if not isinstance(value, str):
            self.error(obj, value)

        conv_func = (lambda c: c) if self.case_sensitive else lambda c: c.lower()
        substring_matching = self.substring_matching
        match_func = (lambda v, c: v in c) if substring_matching else (lambda v, c: c.startswith(v))
        value = conv_func(value)  # type:ignore[no-untyped-call]
        choices = self.values or []
        matches = [match_func(value, conv_func(c)) for c in choices]  # type:ignore[no-untyped-call]
        if sum(matches) == 1:
            for v, m in zip(choices, matches):
                if m:
                    return v

        self.error(obj, value)

    def _info(self, as_rst: bool = False) -> str:
        """Returns a description of the trait."""
        none = " or %s" % ("`None`" if as_rst else "None") if self.allow_none else ""
        case = "sensitive" if self.case_sensitive else "insensitive"
        substr = "substring" if self.substring_matching else "prefix"
        return f"any case-{case} {substr} of {self._choices_str(as_rst)}{none}"

    def info(self) -> str:
        return self._info(as_rst=False)

    def info_rst(self) -> str:
        return self._info(as_rst=True)


class Container(Instance[T]):