def typecheck()

in chz/validators.py [0:0]

• 10 lines of code
• 3 McCabe index (conditional complexity)

def typecheck(self: Any, attr: str) -> None:
    """A fancy type check based on the annotated type of the field."""

    field = self.__chz_fields__[attr.removeprefix("X_")]
    typ = field.x_type

    value = getattr(self, attr)

    if not is_subtype_instance(value, typ):
        # TODO: is_subtype_instance is in a much better place to return diagnostics
        if getattr(typ, "__origin__", None) is Literal:
            raise TypeError(f"Expected {attr} to be {type_repr(typ)}, got {value!r}")
        raise TypeError(
            f"Expected {attr} to be {type_repr(typ)}, got {type_repr(_simplistic_type_of_value(value))}"
        )