Method configure_tuple_base_class

mypy/semanal.py:2703–2723

(self, defn: ClassDef, base: TupleType)

        self.calculate_class_mro(defn, self.object_type)

    def configure_tuple_base_class(self, defn: ClassDef, base: TupleType) -> Instance:
        info = defn.info

        # There may be an existing valid tuple type from previous semanal iterations.
        # Use equality to check if it is the case.
        if info.tuple_type and info.tuple_type != base and not has_placeholder(info.tuple_type):
            self.fail("Class has two incompatible bases derived from tuple", defn)
            defn.has_incompatible_baseclass = True
        if has_placeholder(base):
            self.process_placeholder(
                None, "tuple base", defn, force_progress=base != info.tuple_type
            )
        info.update_tuple_type(base)
        self.setup_alias_type_vars(defn)

        if base.partial_fallback.type.fullname == "builtins.tuple" and not has_placeholder(base):
            # Fallback can only be safely calculated after semantic analysis, since base
            # classes may be incomplete. Postpone the calculation.
            self.schedule_patch(PRIORITY_FALLBACKS, lambda: calculate_tuple_fallback(base))

        return base.partial_fallback

    def set_dummy_mro(self, info: TypeInfo) -> None:
        # Give it an MRO consisting of just the class itself and object.