ref: https://nikkie-ftnext.hatenablog.com/entry/do-not-pass-self-dunder-class-to-builtin-super

infinite_recursion_debug.py

"""
>>> HogeTranslator().foo(1)
MyTranslator foo
108
>>> HogeTranslator().foo(-1)
MyTranslator foo
Translator foo
42
"""


class Translator:
    """
    >>> Translator().foo(1)
    Translator foo
    42
    """

    def foo(self, number):
        print("Translator foo")
        return 42


class MyTranslator(Translator):
    def foo(self, number):
        """
        >>> MyTranslator().foo(1)
        MyTranslator foo
        108
        >>> MyTranslator().foo(-1)
        MyTranslator foo
        Translator foo
        42
        """
        print("MyTranslator foo")
        # print(self.__class__)
        if number > 0:
            return 108
        # 以下はメソッド代入を可能にするが、SpecialMyTranslatorで無限再帰エラーとなる
        # return super(self.__class__, self).foo(number)
        if not isinstance(self, MyTranslator):
            # メソッド代入をサポート（かつ、無限再帰が起きない）
            return super(self.__class__, self).foo(number)
        return super(MyTranslator, self).foo(number)


class HogeTranslator(Translator): ...


HogeTranslator.foo = MyTranslator.foo


class SpecialMyTranslator(MyTranslator):
    """
    >>> SpecialMyTranslator().foo(1)
    MyTranslator foo
    108
    >>> SpecialMyTranslator().foo(-1)
    MyTranslator foo
    Translator foo
    42
    """