Function _expand_stripped_to_children

scripts/update_lib/cmd_auto_mark.py:253–288

Find child-class failures that correspond to stripped parent-class markers. When ``strip_reasonless_expected_failures`` removes a marker from a parent (mixin) class, test failures are reported against the concrete subclasses, not the parent itself. This function maps those child failur

(
    contents: str,
    stripped_tests: set[tuple[str, str]],
    all_failing_tests: set[tuple[str, str]],
)

def _expand_stripped_to_children(
    contents: str,
    stripped_tests: set[tuple[str, str]],
    all_failing_tests: set[tuple[str, str]],
) -> set[tuple[str, str]]:
    """Find child-class failures that correspond to stripped parent-class markers.

    When ``strip_reasonless_expected_failures`` removes a marker from a parent
    (mixin) class, test failures are reported against the concrete subclasses,
    not the parent itself.  This function maps those child failures back so
    they get re-marked (and later consolidated to the parent by
    ``_consolidate_to_parent``).

    Returns the set of ``(class, method)`` pairs from *all_failing_tests* that
    should be re-marked.
    """
    # Direct matches (stripped test itself is a concrete TestCase)
    result = stripped_tests & all_failing_tests

    unmatched = stripped_tests - all_failing_tests
    if not unmatched:
        return result

    tree = ast.parse(contents)
    class_bases, class_methods = _build_inheritance_info(tree)

    for parent_cls, method_name in unmatched:
        if method_name not in class_methods.get(parent_cls, set()):
            continue
        for cls in _find_all_inheritors(
            parent_cls, method_name, class_bases, class_methods
        ):
            if (cls, method_name) in all_failing_tests:
                result.add((cls, method_name))

    return result


def _consolidate_to_parent(