gh-113570: reprlib.repr does not use builtin __repr__ for reshadowed builtins

[georgepittock]

Fixes issue: gh-113570 where objects that reshadow certain builtins would call a specific method and could cause errors, e.g.

import reprlib

class array:
    def __repr__(self):
        return "not array.array!"

reprlib.repr(array())
# previously raised an error, now "not array.array"

This uses a mapping of (module, object name): method to map to the right method, as mentioned in the issue.

[ghost]

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[sobolevn]

Please, also take a look at this doctest failure:

 Document: library/reprlib
-------------------------
**********************************************************************
File "library/reprlib.rst", line 481, in default
Failed example:
    import reprlib
    import sys

    class MyRepr(reprlib.Repr):

        def repr_TextIOWrapper(self, obj, level):
            if obj.name in {'<stdin>', '<stdout>', '<stderr>'}:
                return obj.name
            return repr(obj)

    aRepr = MyRepr()
    print(aRepr.repr(sys.stdin))         # prints '<stdin>'
Expected:
    <stdin>
Got:
    <_io.TextIOWr...oding='utf-8'>
1 items passed all tests:
   8 tests in indent
**********************************************************************
1 items had failures:
   1 of   7 in default
15 tests in 2 items.
14 passed and 1 failed.
***Test Failed*** 1 failures.

[georgepittock]

To handle the failing doctest some more edge cases need to be handled so cases where someone has defined a custom method still work.

To keep something somewhat similar to what we had there a (4) cases. I am saying there is a predefined method for an object of type a if the class has a method repr_x.

1. No predefined method
2. There is a predefined method that is not in our lookup (user defined in a subclass)
3. There is a predefined method, that is in our lookup and has the same module and type as what we expect
4. There is a predefined method, that is in our lookup and has a different module and type as what we expect (reprlib (used by pytest) infers builtin types based on class __name__ #113570)

In cases 1 and 4 we will return self.repr_instance(x, level), but in 2 and 3 getattr(self, predefined_method_name)(x, level)

I have added an explicit unit test for case 2 in my latest commit, cases 1, 3 and 4 are already there.

[georgepittock]

@sobolevn are you able to look at the updated changes from your comments?

[sobolevn]

Generally, looks ok to me, but there are several nitpicks :)

[georgepittock]

Fixed those two comments @sobolevn

[sobolevn]

This is the last comment, thank you! :)

[georgepittock]

That's sorted @sobolevn !

[georgepittock]

Is this all good now @sobolevn ?

[serhiy-storchaka]

Please remove unrelated style changes.

[serhiy-storchaka]

Thank you for your update, @georgepittock. One minor nitpick. The rest LGTM.

[georgepittock]

CI failure looks unrelated, merging main into branch so trigger CI again...

[miss-islington-app]

Thanks @georgepittock for the PR, and @serhiy-storchaka for merging it 🌮🎉.. I'm working now to backport this PR to: 3.12, 3.13.
🐍🍒⛏🤖

[bedevere-app]

GH-125654 is a backport of this pull request to the 3.13 branch.

[bedevere-app]

GH-125655 is a backport of this pull request to the 3.12 branch.