gh-153896: Deduplicate unhashable Literal params

[Maxinho96]

• Issue: Literal[...] deduplication silently skips when values are unhashable #153896

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[python-cla-bot]

All commit authors signed the Contributor License Agreement.

[picnixz]

#153913 was just open a few minutes ago, but maybe @sobolevn wants relinquish his right to the PR

[sobolevn]

Sure, since this is the first contribution by @Maxinho96, I would prefer to merge their PR :)

[bedevere-app]

Most changes to Python require a NEWS entry. Add one using the blurb_it web app or the blurb command-line tool.

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[sobolevn]

⚽️ I am a huge ⚪️🔵 Lazio 🦅 fan

Oh no, closing! 😱
I am AS Roma fan 😱

I am joking, obviously (not about the Roma part) :)
Thanks for the PR! And welcome :)

[picnixz]

We ususally want lines under 80 charactesr, so I suggest that you rename value_and_type_parameters to a shorter name or you use the same format as Nikita:

    parameters = tuple(
        p
        for p, _ in _deduplicate(
            list(_value_and_type_iter(parameters)),
            unhashable_fallback=True,
        )
    )

[Maxinho96]

6e95e84

[Maxinho96]

For the future: how do I enforce the correct formatting? The pre-commit hook passed for some reason. I see it uses ruff, but if I run it one the codebase it changes all the files

[picnixz]

Unfortunately, this is a manual task =/ we do have some parts of the stdlib with ruff configs, but for historical reasons, we don't enforce style on old files (for maintenance and diff purposes) and only try to enforce them for new code (so code you add, or code you change around). See PEP-7/PEP-8 guidelines (while they are guidelines, sometimes we need to break them because it's not consistent).

What we aim for:

• Minimal diff in general.
• If possible PEP-7/PEP-8 style if this doesn't introduce too many unrelated changes.
• If not psosible, keep consistent style.

[tomasr8]

@Maxinho96 Make sure to add a NEWS entry as well :)

[Maxinho96]

Oh no, closing! 😱 I am AS Roma fan 😱

@sobolevn lol what are the chances? I forgive you for your sins since you kindly let me contribute, thanks! 🙏🏻

[ZeroIntensity]

Thanks! This looks good to me.

I think backporting makes sense here. It's unlikely that people are relying on this in a way that would break code; if anything, people could have been running their own deduplication pass on __args__, but that won't be broken by this fix.

[miss-islington-app]

Thanks @Maxinho96 for the PR, and @ZeroIntensity for merging it 🌮🎉.. I'm working now to backport this PR to: 3.13, 3.14, 3.15.
🐍🍒⛏🤖

[bedevere-app]

GH-153955 is a backport of this pull request to the 3.15 branch.

[bedevere-app]

GH-153956 is a backport of this pull request to the 3.14 branch.

[bedevere-app]

GH-153957 is a backport of this pull request to the 3.13 branch.