Change Request: (Consider moving .eslintcache to node_modules/.cache)

[recallwei]

ESLint version

v8.0.0

What problem do you want to solve?

Now, I should add .eslintcache to .gitignore manually.
Also, this file should not be in the project root dir.

What do you think is the correct solution?

Like Prettier, Store in node_modules/.cache seems a great solution.

Participation

• I am willing to submit a pull request for this change.

Additional comments

No response

[aladdin-add]

I'm 👍 to this. However, it's a breaking change, so we cannot accept it in v9(it's in rc). I think we can change it in v10.

Would like to hear from other team members. @eslint/eslint-team

[nzakas]

I don't think there's a good reason to change the location of the cache file. Some users actually do check in .eslintcache to their repository for CI purposes, so I don't think it's safe to either assume that most people don't want that or to put it into a location that is always gitignored by default.

[JoshuaKGoldberg]

Some users actually do check in .eslintcache to their repository for CI purposes

🤔 is that... advisable? My impression was that the slice of users who'd want to do such a thing is pretty small. This is all anecdotal and I'd want to know if I'm wrong anywhere:

• Most repositories that include artifacts don't check them in, based on the reasoning that they can clutter changes (e.g. tsconfig.tsbuildinfo)
• Most repositories that have performance issues get it from cross-file linting such as eslint-plugin-import or typescript-eslint type-checked rules. Given that caching doesn't work well with cross-file lint rules (e.g. Docs: explain whether type-aware linting is safe to use with eslint --cache typescript-eslint/typescript-eslint#4694), that swathe of repositories likely shouldn't be using it at all
  • This, in particular, I would like to be corrected on if I'm wrong 🙂

I believe the ecosystem norm is to put artifacts in node_modules/.cache or some similar location. If that's right, then my instinct would be that the default for caching should be the ecosystem norm, with an opt-in option to move to a new location like .eslint-cache.

[nzakas]

🤔 is that... advisable?

Folks do this to speed up their CI. There's even an RFC aimed at making this easier:
eslint/rfcs#114

[recallwei]

Most of the projects do not use cache and CI. Is it possible to add some custom config to specify the location of the cache file?

[nzakas]

@recallwei I don't think you can make any assertion about what most projects do, and even if you could, that doesn't mean we don't consider those use cases.

There is already a --cache-location flag that you can use to place the cache file into node_modules if you want.

[fasttime]

So, if the directory where eslint runs does not contain a package.json file or a node_modules directory, what should happen?