refactor(linter/plugins): enable TS strict option

[sapphi-red]

Enable TypeScript strict option in apps/oxlint.

[sapphi-red]

• fix(linter/plugins): define RegExp.escape for tsc #20077
• docs(linter/plugins): move comment about "bivariance hack" into generated code #20082
• fix(linter/plugins): fix types for walkProgram and walkProgramWithCfg #20081
• refactor(linter/plugins): debug assert that values passed via NAPI are not undefined #20070
• refactor(linter/plugins): clarify types #20069
• test(linter/plugins): add types test for VisitorObject #20066
• refactor(linter/plugins): enable TS strict option #19675 👈 (View in Graphite)
• fix(linter/plugins): fix type definition for VisitorObject #20065
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 4 untouched benchmarks
⏩ 46 skipped benchmarks¹

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_{Comparing 02-24-chore_apps_oxlint_enable_typescript_strict_option (36ca452) with main (0722721)}

Footnotes

1. 46 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. ↩

[Copilot]

Pull request overview

This PR fixes TypeScript type errors in the linter's JS plugin system by enabling strict mode and implementing a bivariance hack for visitor objects. The bivariance hack allows visitor functions with specific node types (e.g., CallExpression) to be assigned to properties expecting more generic node types, which is necessary for the plugin system to work correctly with TypeScript's strict type checking.

Changes:

• Enabled TypeScript strict mode in apps/oxlint/tsconfig.json to catch type issues
• Implemented bivariance hack pattern for VisitorObject type to fix variance issues with visitor function parameters
• Added type assertions and nullish coalescing operators to satisfy strict null checks
• Added type definition tests to verify visitor object compatibility

Reviewed changes

Copilot reviewed 13 out of 16 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tasks/ast_tools/src/generators/raw_transfer.rs	CRITICAL BUGS: Added incorrect import and type for NodeOrToken in generated deserialize type definitions
tasks/ast_tools/src/generators/estree_visit.rs	Implemented bivariance hack pattern for visitor types to allow contravariant parameter types
apps/oxlint/src-js/generated/visitor.d.ts	Generated visitor types with bivariance hack implementation
apps/oxlint/src-js/generated/deserialize.d.ts	Generated with incorrect NodeOrToken type usage (from raw_transfer.rs bugs)
apps/oxlint/src-js/visitor.test-d.ts	Added type-level tests to validate visitor object type compatibility
apps/oxlint/src-js/plugins/visitor.ts	Added type assertions for strict mode compatibility
apps/oxlint/src-js/plugins/cfg.ts	Added type assertions for strict mode compatibility
apps/oxlint/src-js/cli.ts	Added undefined handling with nullish coalescing for strict null checks
apps/oxlint/src-js/package/rule_tester.ts	Improved function signatures with proper this parameter typing and disabled unbound-method warnings
apps/oxlint/conformance/src/rule_tester.ts	Added oxlint-disable comment for intentional unbound method usage
apps/oxlint/tsconfig.json	Enabled strict mode and added node types
napi/parser/tsconfig.json	Added node types configuration
napi/transform/tsconfig.json	Added node types configuration
apps/oxfmt/tsconfig.json	Added node types configuration
apps/oxlint/package.json	Added @type-challenges/utils dependency for type tests
pnpm-lock.yaml	Updated lock file with new dependency

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

[Copilot]

Pull request overview

Copilot reviewed 8 out of 9 changed files in this pull request and generated 3 comments.

Comments suppressed due to low confidence (1)

apps/oxlint/conformance/src/rule_tester.ts:112

• test.before = function (this) { ... } relies on a this parameter without a type annotation. With TS strict (enables noImplicitThis), this form typically fails type-checking. Add an explicit this type (e.g. function (this: T) { ... } / unknown) and keep originalBefore typed with the same this so hooks that depend on their this context remain correctly typed.

    const originalBefore = test.before as () => void;
    test.before = function (this) {
      setCurrentTest(clonedTest);
      originalBefore!.call(this);
    };

[graphite-app]

Merge activity

• Mar 6, 5:29 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Mar 6, 5:37 PM UTC: Merged by the Graphite merge queue.