For incompatible attribute assignment, show class that defines attribute

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
python
Domain
devtools

Research direction

Use the examples in the issue to define when incompatible-attribute errors should name the defining class, and whether the original file and line should be included. The issue names no files or tests, so first locate the incompatible-attribute diagnostic and its existing coverage; done means the selected cases produce the intended message without unnecessary verbosity in same-class assignments.

Written by the indexing model from the issue text.

Description

feature good-second-issue priority-1-normal topic-usability

It would be nice to display the class that defines the attribute when we assign an incompatible value to an attribute:

class A:
    a = 1

class B(A):
    a = ''  # Show that 'a' was defined in 'A' (in addition to the current message)

class C(A): pass

c = C()
c.a = ''   # Again, maybe show that 'a' was defined in 'A'

Maybe also show the file and line on which the attribute was originally defined. However, we probably don't want these verbose messages in the body of a class if the attribute definition is in the same class, as the error is probably clear enough based on immediate context:

class A:
    a = 1

    def f(self) -> None:
        self.a = ''   # The current message is probably just fine, as the context is clear
Dominant language
Python
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Merged PRs (30d)
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