Support `Linter` API

[kazupon]

ESLint is providing Linter as low level linting API.
Some ESLint ecosytem is providing library and tools with using it.

For example, eslint-vitest-rule-tester is providing rule tester, which is more useful than RuleTester
https://github.com/antfu-collective/eslint-vitest-rule-tester/blob/main/src/rule-tester.ts#L29

[bradzacher]

This doesn't really make sense for oxlint, IMO, because the internals are all in rust. It would probably require a pretty major rewrite of things to separate the internals to match the Linter API and allow it to be exposed to JS.

Additionally the surface of the class is pretty large and flexible - there's a whole lot to possibly cover.

The better framing for the request here would be to detail your usecase and expected requirements. Eg "I would like to do X so and I would like to prolose that a lower level API that exposes foo would let me do that"

[kazupon]

The better framing for the request here would be to detail your usecase and expected requirements. Eg "I would like to do X so and I would like to prolose that a lower level API that exposes foo would let me do that"

You're right, the Issue description was insufficient.

eslint-vitest-rule-tester is a Rule Tester integrated with vitest that provides an API similar to RuleTester.
Internally, it uses the Linter provided by ESLint and offers features not available in RuleTester (e.g, onResult hook).

I believe that if oxlint provides something compatible with ESLint's Linter, eslint-vitest-rule-tester could also serve as oxlint's rule tester without any changes.

This doesn't really make sense for oxlint, IMO, because the internals are all in rust. It would probably require a pretty major rewrite of things to separate the internals to match the Linter API and allow it to be exposed to JS.

I also understand that large-scale rewrites may be necessary.
ESLint's RuleTester internally uses a Linter to provide it functionality.
RuleTester provided by oxlint is the class, implemented using helper/utils

I seem that Oxlint could also provide a Linter using the same implementation and approach.

oxlint has other higher-priority tasks. Since oxlint already provides RuleTester, we can use it to test rules without needing eslint-vite-rule-tester.

[Boshen]

Our entry point is Node.js, we can provide APIs through napi, it'll just be a lot of work.

[bradzacher]

Internally, it uses the Linter provided by ESLint

That's the bit to really dig into. What does it use?

Cos like I said the eslint Linter class is a pretty powerful and flexible thing. Replicating it isn't going to be easy cos oxlint isn't architected even remotely similarly to eslint

Like Boshen said - its a napi.rs API so anything can be built and surfaced - but yeah we wouldn't want to boil the ocean if all we need is one small feature.

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And of course the alternative question to ask.

Do we really need a separate Linter-like API when we could just replicate eslint-vitest-rule-tester's extra features in oxlint's RuleTester?

Is there a specific reason you need the low-level API so you can build your own rule tester? Or would a fully-featured rule tester out of the box be fine?