feat(linter/plugins): rule options

[lilnasy]

• Implements Linter plugins: Support options for JS rules #14825
• Rebased feat(linter): Add support for options for jsPlugins #15822. Refactored. Pruned the slop. Tests passing.

Big changes from the original approach

• Options IDs are stored in their own arrays. This was laid out in refactor(linter/plugins): prepare for rule options #16158. The original approach was to store ruleId-optionId pairs as tuples in an array - several heap allocated objects and excessive pointer indirection.
• The rust code populates the options by calling a new JS callback named setupConfigs(). I expect we would use this callback for more plugin related data, including settings which are currently implemented in a hacky way.
• Investigate a refactor to avoid requiring a mutable reference to ExternalPluginStore everywhere.

Smaller Changes

• Removed the extra fixture ("working version"). There were no meaningful changes compared to the first fixture. Probably slop.

[Copilot]

Pull request overview

This PR implements rule options support for external JavaScript plugins in the linter. It introduces an ExternalOptionsId type to track and pass rule-specific configuration options from Rust to JavaScript plugins, allowing JS plugin rules to receive configuration parameters similar to ESLint rule options.

Key changes:

• Added ExternalOptionsId type and options storage to ExternalPluginStore with index 0 reserved for "no options"
• Updated external rule signatures from (ExternalRuleId, AllowWarnDeny) to (ExternalRuleId, ExternalOptionsId, AllowWarnDeny) throughout the codebase
• Implemented options serialization/deserialization flow between Rust and JavaScript using OnceLock for thread-safe caching

Reviewed changes

Copilot reviewed 23 out of 24 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
crates/oxc_linter/src/external_plugin_store.rs	Added ExternalOptionsId type and options storage with index 0 reserved for empty/null options
crates/oxc_linter/src/external_linter.rs	Updated callback signature to include options_ids parameter
crates/oxc_linter/src/lib.rs	Updated external rule handling to pass options IDs to JS side
crates/oxc_linter/src/config/rules.rs	Modified override_rules to track options alongside severity; added comprehensive tests
crates/oxc_linter/src/config/config_store.rs	Updated rule storage and override logic to handle options IDs; added override precedence test
crates/oxc_linter/src/config/config_builder.rs	Updated builder to accept mutable reference to external plugin store for options registration
crates/oxc_linter/src/config/mod.rs	Updated test to use mutable external plugin store
crates/oxc_linter/src/tester.rs	Updated to pass mutable reference to external plugin store
crates/oxc_language_server/src/linter/server_linter.rs	Updated config building calls to use mutable external plugin store
tasks/benchmark/benches/linter.rs	Updated benchmark to use mutable external plugin store
napi/playground/src/lib.rs	Updated playground to properly share external plugin store between config building and linter creation
apps/oxlint/src/run.rs	Added OnceLock-based caching for serialized options JSON and export function for JS
apps/oxlint/src/lint.rs	Added serialization of external options after config building
apps/oxlint/src/js_plugins/external_linter.rs	Updated wrapper to forward options IDs to JS callback
apps/oxlint/src-js/plugins/options.ts	Added options initialization logic and storage
apps/oxlint/src-js/plugins/load.ts	Duplicated options initialization logic (should be removed)
apps/oxlint/src-js/plugins/lint.ts	Added lazy options initialization and options ID handling; duplicate ruleIndex assignment
apps/oxlint/src-js/cli.ts	Updated wrapper to forward options IDs parameter
apps/oxlint/src-js/bindings.js	Exported getExternalRuleOptions function
apps/oxlint/src-js/bindings.d.ts	Added TypeScript declaration for getExternalRuleOptions
apps/oxlint/test/fixtures/custom_plugin_with_options/*	Added integration test fixture for external plugin with options

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[codspeed-hq]

CodSpeed Performance Report

Merging #16215 will not alter performance

_{Comparing lilnasy:js-plugin-options (736841b) with main (decf2ad)¹}

Summary

✅ 42 untouched
⏩ 3 skipped²

Footnotes

1. No successful run was found on main (10a1737) during the generation of this report, so decf2ad was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[overlookmotel]

Just a note: As I mentioned on Discord, I don't think we should worry about merging options with default options in this first PR - can leave that to a follow-on. But FYI I've implemented the merging logic in #16217 because I needed it for the rule tester.

[overlookmotel]

Refactor to avoid requiring a mutable reference to ExternalPluginStore everywhere.

I know it was me that said this should be possible, but I could very well be wrong. If it's not possible, don't worry about it.

[Copilot]

Pull request overview

Copilot reviewed 23 out of 24 changed files in this pull request and generated 2 comments.

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[overlookmotel]

I've pushed some changes. All nits and code style apart from these ones which are more substantive:

• 330604e
• 63881d7
• 8ecc071
• 8f2a6e2
• 736841b

Even those ones are all still minor though.

Great work! This will be in today's release.