[CI/Build] drop support for Python 3.8 EOL

[aarnphm]

As Python 3.8 reaches EOL, this PR would be a starting point to remove potential code branch on 3.8 only.

I'm still working through all of the code, but this would be a starting point for CI.

Depends on #8469, and wait til PyTorch drop 3.8 support

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[DarkLight1337]

Do we have pyupgrade enabled in the settings for ruff? Would be great if we could use it to get rid of legacy code.

[aarnphm]

Do we have pyupgrade enabled in the settings for ruff? Would be great if we could use it to get rid of legacy code.

I think we can update to latest ruff and use pyupgrade. But I feel like that introduce a lot of merge conflict for other higher priority PR.

For these CI PR would probably be best to run before releasing a new version. What do you think?

ps: I can add ruff tool, but won't run it if that works better.

[DarkLight1337]

Currently we use yapf for formatting, and ruff only for linting. I think adding pyupgrade lint rules should not cause many changes to the code.

[DarkLight1337]

I think adding pyupgrade lint rules should not cause many changes to the code.

OK, I stand corrected... maybe we can turn on just a subset of the rules ?

[DarkLight1337]

In particular, f-string formatting seems to be responsible for most of the diffs, so try turning that off.

[aarnphm]

yes, will revert 182d0d7

[aarnphm]

fwiw https://docs.astral.sh/ruff/rules/#pyupgrade-up we can exclude f-string format?

[aarnphm]

Also are there any specific reason that we locked ruff to 0.1? it is pretty old?

[DarkLight1337]

Upgrading ruff may add new rules from the categories that we've currently enabled. Let's do that in a separate PR to avoid introducing a huge amount of diffs.

[DarkLight1337]

fwiw https://docs.astral.sh/ruff/rules/#pyupgrade-up we can exclude f-string format?

We can specify the rules to ignore inside the list in tool.ruff.lint.ignore.

[DarkLight1337]

Since we might not want to drop Python 3.8 immediately, it's probably better to work on upgrading ruff first in another PR.

[aarnphm]

#8469 cc @DarkLight1337

[DarkLight1337]

Now that Python 3.8 has reached EOL, let's resume work on this.

[DarkLight1337]

Heads up that PyTorch 2.5.0 has officially dropped Python 3.8 as well. Can you update this PR? (Probably easier to revert the non-CI/CD file changes and apply the linter on latest main)

[aarnphm]

yep I will revisit this this weekend, sorry work and other stuff got caught up

[DarkLight1337]

@aarnphm any update? Otherwise, we'll work on this issue in #10038 instead.

[aarnphm]

Oh I think I already push on my end

[DarkLight1337]

Please fix the linter errors. There are also a couple places where we use sys.version_info, so it would be great if you could prune the 3.8-only code!

[mergify[bot]]

This pull request has merge conflicts that must be resolved before it can be merged. @aarnphm please rebase it. https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[aarnphm]

cc @DarkLight1337 PTAL

[DarkLight1337]

Please take a look at the doc failure.

There are also a couple places where we use sys.version_info, so it would be great if you could prune the 3.8-only code!

And also this.

[aarnphm]

Hmm I already remove all sys.version_info compat for 3.8

[DarkLight1337]

Hmm I already remove all sys.version_info compat for 3.8

How about sys.version_info < (3, 9)?

[aarnphm]

hmm thats weird I thought I already fixed it, anw