feat(eslint-plugin): [no-unsafe-enum-comparison] handles switch cases

[Zamiell]

PR Checklist

• Addresses an existing open issue: fixes [no-unsafe-enum-comparison] consider evaluating switch statements #7509
• That issue was marked as accepting prs
• Steps in Contributing were taken

Overview

Hello, co-author of the no-unsafe-enum-comparison rule here.

Currently, he no-unsafe-enum-comparison rule handles comparisons (e.g. BinaryExpression) but it does not handle switch statements. My PR makes the rule handle both.

This was an oversight in my original design of this rule, and I consider this to be a bug. However, I have marked the PR as feat instead of fix to be more conservative; feel free to change it if you wish.

Code Change Summary

I refactored the logic in the BinaryExpression selector and put it inside of a function called isMismatchedComparison.
Then, I can call that function from multiple selectors. The changes should be pretty straightforward to understand.

Other Notes

I have reworked the documentation for this rule a bit, as the original text is now no longer accurate, because TypeScript has made number enums more safe in version 5.0. Thus, I rewrote the document to focus on the string case, adding a line to emphasize that the rule is still useful if you choose to use string enums over number enums.

[typescript-eslint]

Thanks for the PR, @Zamiell!

typescript-eslint is a 100% community driven project, and we are incredibly grateful that you are contributing to that community.

The core maintainers work on this in their personal time, so please understand that it may not be possible for them to review your work immediately.

Thanks again!

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[Zamiell]

Oh, interestingly enough, the new version of the rule found a bug at packages/eslint-plugin/src/rules/no-unnecessary-type-constraint.ts.
I've also taken care of that in this PR so that CI passes.

(Well, CI passes except for codecov/patch, not sure what to do about that one.)

[JoshuaKGoldberg]

Great stuff, thanks for such a thorough look & overhaul! 🔥

A few requests for changes, and some nitpicks I'd like to hear your thoughts on.

[Zamiell]

theres some bogus stuff going on in CI, i think a maintainer needs to look at this, as it looks unrelated to my PR.

[JoshuaKGoldberg]

Oop, I'd meant to merge changes from main after merging #7691 but I don't think I have permissions to push to your branch @Zamiell. Pushed to here instead: https://github.com/JoshuaKGoldberg/typescript-eslint/tree/enum-comparison-switch-merge

I think the lint failure in ErrorsViewer.tsx on the switch (severity) is an existing bug in the rule that just so happens to be exposed by this PR. Something imported with import type might not be a value that can actually be runtime-imported. If this is an existing bug, I think it'd be reasonable to eslint-disable it in this PR and file a followup issue. WDYT?

Otherwise 👍 LGTM for merging! We'd want to file a followup issue to get #7691's suggest: ... in switch statements too.

[Zamiell]

how do i give you permission? otherwise, just merge whatever changes from your own branch, as it doesn't matter to me

[JoshuaKGoldberg]

It's on the bottom-right of the page, at the bottom of the right sidebar:

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/allowing-changes-to-a-pull-request-branch-created-from-a-fork is the closest docs page I could find on docs.github.com.

I would prefer to get the changes in this PR so that it's easier to find from the Git history. And you deserve direct/primary author attribution as you've put a lot of great work into this PR! 😄

[Zamiell]

@JoshuaKGoldberg That button doesn't show up for me. Can you just use the changes from your own branch instead?

[JoshuaKGoldberg]

Sure, no worries: #7898. I'm guessing you're not seeing the permissions because this PR was sent from an organization (IsaacScript). Either you don't have permissions to enable maintainer merging on that org or that's not doable on GitHub altogether. I don't recall if that's the case.

[Zamiell]

ok, should i close this PR now?

[JoshuaKGoldberg]

👍 yup! Just merged #7898.

Thanks again as always @Zamiell!