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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"The help function shows incorrect signature for subclass","articleBody":"# Bug report\r\n\r\nWith the following class hierarchy:\r\n\r\n```py\r\nclass A0:\r\n    def __new__(cls, *args, **kw):\r\n        return super().__new__(cls)\r\n    def __init__(self, *args, **kw):\r\n        super().__init__()\r\n\r\nclass A1(A0):\r\n    def __init__(self, a, b):\r\n        super().__init__()\r\n        self.a = a\r\n        self.b = b\r\n\r\nclass A2(A1):\r\n    c = None\r\n\r\n```\r\n\r\n`help(A2)` shows the wrong signature for instantiating A2 as `A2(*args, **kw)` instead of the expected `A2(a, b)`, despite the fact that is shows the correct signature for `__init__`:\r\n\r\n```\r\nHelp on class A2 in module __main__:\r\n\r\nclass A2(A1)\r\n |  A2(*args, **kw)\r\n |  \r\n |  Method resolution order:\r\n |      A2\r\n |      A1\r\n |      A0\r\n |      builtins.object\r\n |  \r\n |  Data and other attributes defined here:\r\n |  \r\n |  c = None\r\n |  \r\n |  ----------------------------------------------------------------------\r\n |  Methods inherited from A1:\r\n |  \r\n |  __init__(self, a, b)\r\n |      Initialize self.  See help(type(self)) for accurate signature.\r\n |  \r\n |  ----------------------------------------------------------------------\r\n |  Static methods inherited from A0:\r\n |  \r\n |  __new__(cls, *args, **kw)\r\n |      Create and return a new object.  See help(type) for accurate signature.\r\n |  \r\n...\r\n```\r\n\r\nNote that `help(A1)` works correctly and shows the correct signature as `A1(a, b)`:\r\n\r\n```\r\nHelp on class A1 in module __main__:\r\n\r\nclass A1(A0)\r\n |  A1(a, b)\r\n |  \r\n |  Method resolution order:\r\n |      A1\r\n |      A0\r\n |      builtins.object\r\n |  \r\n |  Methods defined here:\r\n |  \r\n |  __init__(self, a, b)\r\n |      Initialize self.  See help(type(self)) for accurate signature.\r\n |  \r\n |  ----------------------------------------------------------------------\r\n |  Static methods inherited from A0:\r\n |  \r\n |  __new__(cls, *args, **kw)\r\n |      Create and return a new object.  See help(type) for accurate signature.\r\n |  \r\n...\r\n```\r\n\r\nThis doesn't seem to be an issue if `__new__` is not defined on A0, or if A1 redefines `__new__` with the same signature as `__init__`.\r\n\r\n# Your environment\r\n\r\n\u003c!-- Include as many relevant details as possible about the environment you experienced the bug in --\u003e\r\n\r\n- CPython versions tested on: 3.11.3+\r\n- Operating system and architecture: Linux x86\r\n\r\n\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-105217\n* gh-105257\n* gh-105274\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/danpascu","@type":"Person","name":"danpascu"},"datePublished":"2023-05-30T05:09:47.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":25},"url":"https://github.com/105080/cpython/issues/105080"}