Function _collect_base_attrs_broken

src/attr/_make.py:351–376

Collect attr.ibs from base classes of *cls*, except *taken_attr_names*. N.B. *taken_attr_names* will be mutated. Adhere to the old incorrect behavior. Notably it collects from the front and considers inherited attributes which leads to the buggy behavior reported in #428.

(cls, taken_attr_names)

def _collect_base_attrs_broken(cls, taken_attr_names):
    """
    Collect attr.ibs from base classes of *cls*, except *taken_attr_names*.

    N.B. *taken_attr_names* will be mutated.

    Adhere to the old incorrect behavior.

    Notably it collects from the front and considers inherited attributes which
    leads to the buggy behavior reported in #428.
    """
    base_attrs = []
    base_attr_map = {}  # A dictionary of base attrs to their classes.

    # Traverse the MRO and collect attributes.
    for base_cls in cls.__mro__[1:-1]:
        for a in getattr(base_cls, "__attrs_attrs__", []):
            if a.name in taken_attr_names:
                continue

            a = a.evolve(inherited=True)  # noqa: PLW2901
            taken_attr_names.add(a.name)
            base_attrs.append(a)
            base_attr_map[a.name] = base_cls

    return base_attrs, base_attr_map


def _transform_attrs(