Hovering over instance of derived class shows docstring for base class

[johndoknjas]

Environment data

• Pylance version: 2025.6.2
• OS and version: Mac 14.7.5
• Python version (& distribution if applicable, e.g. Anaconda): 3.13

Code Snippet

def test():
    raise NotImplementedError()

Repro Steps

1. Hover over the NotImplementedError in the code snippet within vscode.

Expected behavior

Docstring for NotImplementedError would appear in the popup.

Actual behavior

Docstring for base class BaseException appears:

Logs

XXX

[github-actions]

Hi @johndoknjas, I'm an AI Support assistant here to help with your issue. While the team reviews your request, I wanted to provide some possible tips and documentation that might help you in the meantime.

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Duplicate Issues – These issues appear to be duplicates of your report.

• Docstring from base class appears instead of derived class constructor for Line. How best to handle class hierarchies #7303

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Potential Duplicate Issues – These issues may be duplicates of your report, but may differ in some of the details.

• Hover popup shows B.foo docstring instead of inherited A.foo in multiple inheritance. Mouse over docstring is not consistent with inspect.getdoc when using multiple inheritance #5821

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The team will respond to your issue shortly. Please note this is a trial feature and may not be fully accurate. I hope these suggestions are helpful in the meantime. If this comment helped you, please give it a 👍. If the suggestion was not helpful or was incorrect, please give it a 👎. Your feedback helps us improve!

[rchiodo]

This is a function of how NotImplementedError isn't actually defined in a Python file. The docstring then reverts to the closest class that we can find the docstring for.

We might be able to generate these in our builtins.pyi before shipping I'd think.

[heejaechang]

Retained repro workspace: https://github.com/heejaechang/pylance-repro/tree/main/pylance-issues/7970