[skip chg] Migrate linting and formatting to oxc

.github/agents/language-package.agent.md

@@ -49,7 +49,7 @@ Run these commands scoped to the files under review and include the results in y
 
 - **Tests**: `pnpm vitest run <test-file>` — confirm the co-located test file exists and passes.
 - **Type check**: `pnpm tsc --noEmit -p <package>/tsconfig.json` — confirm no type errors.
-- **Lint**: `pnpm eslint <file>` — confirm no lint violations.
+- **Lint**: `pnpm oxlint <file>` — confirm no lint violations.
 
 If any of these fail, include the failure output as a finding.
 

.github/workflows/changes.yml

@@ -10,7 +10,7 @@ permissions:
 
 jobs:
   changes:
-    if: ${{ github.actor != 'dependabot[bot]' && !startsWith(github.head_ref, 'publish/') }}
+    if: ${{ github.actor != 'dependabot[bot]' && !startsWith(github.head_ref, 'publish/') && !contains(github.event.pull_request.title, '[skip chg]') }}
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4

.oxfmtrc.json

@@ -0,0 +1,21 @@
+{
+  "$schema": "./node_modules/oxfmt/configuration_schema.json",
+  "printWidth": 80,
+  "sortImports": true,
+  "sortPackageJson": false,
+  "ignorePatterns": [
+    "pnpm-lock.yaml",
+    "packages/babel-plugin-alloy/test/fixtures/**/*",
+    "packages/babel-plugin-jsx-dom-expressions/test/__*_fixtures__/**/*",
+    "packages/babel-plugin-jsx-dom-expressions/**",
+    "packages/docs/dist",
+    "packages/docs/dist-build",
+    "packages/docs/public",
+    "packages/docs/docs",
+    "packages/docs/src",
+    "packages/csharp/src/builtins",
+    ".chronus/changes/",
+    "CHANGELOG.md",
+    "*.generated.*"
+  ]
+}

.oxlintrc.json

@@ -0,0 +1,96 @@
+{
+  "$schema": "./node_modules/oxlint/configuration_schema.json",
+  "plugins": ["typescript", "vitest"],
+  "categories": {
+    "correctness": "error"
+  },
+  "ignorePatterns": [
+    "**/*.d.ts",
+    "**/dist/**/*",
+    "**/.temp/**/*",
+    "packages/*/vitest.config.ts",
+    "packages/*/babel.config.cjs",
+    "packages/babel-plugin-jsx-dom-expressions/**/*",
+    "packages/babel-plugin-alloy/**/*",
+    "packages/babel-preset-alloy/**/*",
+    "packages/devtools/**/*",
+    "packages/docs/**/*",
+    "samples/**/*",
+    "**/scripts/**/*",
+    "**/cmd/**/*"
+  ],
+  "rules": {
+    "no-console": "warn",
+    "typescript/no-explicit-any": "off",
+    "typescript/no-empty-object-type": "off",
+    "no-unused-vars": [
+      "warn",
+      {
+        "varsIgnorePattern": "^_",
+        "argsIgnorePattern": ".*",
+        "caughtErrorsIgnorePattern": ".*",
+        "ignoreRestSiblings": true
+      }
+    ],
+    "prefer-const": "warn",
+    "eqeqeq": ["warn", "always", { "null": "ignore" }],
+
+    // Rules oxlint enables by default (via the `correctness` category) that
+    // were not enforced by the previous ESLint setup. Disabled so the
+    // migration does not introduce new errors.
+    // `no-useless-catch`: the codebase intentionally re-throws in `try/catch`
+    // to preserve call stacks (previously suppressed inline everywhere).
+    "no-useless-catch": "off",
+    "no-useless-rename": "off",
+    "vitest/expect-expect": "off",
+    "vitest/no-conditional-expect": "off",
+    "vitest/require-mock-type-parameters": "off",
+    "vitest/require-to-throw-message": "off",
+    "vitest/valid-title": "off",
+
+    // Type-aware linting (via oxlint-tsgolint, enabled by `--type-aware`).
+    // We only opt into `no-floating-promises` to match the previous ESLint
+    // setup. The `--type-aware` flag only activates the type-aware rules that
+    // belong to an enabled category, so the list below is exactly the
+    // type-aware rules in `correctness` (minus `no-floating-promises`); all
+    // other type-aware rules live in categories that are off by default.
+    // Remove an entry here to progressively adopt more type-aware rules.
+    "typescript/no-floating-promises": "warn",
+    "typescript/await-thenable": "off",
+    "typescript/no-array-delete": "off",
+    "typescript/no-base-to-string": "off",
+    "typescript/no-duplicate-type-constituents": "off",
+    "typescript/no-for-in-array": "off",
+    "typescript/no-implied-eval": "off",
+    "typescript/no-meaningless-void-operator": "off",
+    "typescript/no-misused-spread": "off",
+    "typescript/no-redundant-type-constituents": "off",
+    "typescript/no-unsafe-unary-minus": "off",
+    "typescript/no-useless-default-assignment": "off",
+    "typescript/require-array-sort-compare": "off",
+    "typescript/restrict-template-expressions": "off",
+    "typescript/triple-slash-reference": "off",
+    "typescript/unbound-method": "off"
+  },
+  "overrides": [
+    {
+      "files": ["packages/trace-cli/**/*.ts"],
+      "rules": {
+        "no-console": "off"
+      }
+    },
+    {
+      "files": ["**/*.test.ts"],
+      "rules": {
+        "vitest/no-focused-tests": "warn",
+        "vitest/no-identical-title": "error",
+        "vitest/no-commented-out-tests": "warn",
+        "vitest/no-import-node-test": "warn",
+        "vitest/require-local-test-context-for-concurrent-snapshots": "warn",
+        "vitest/valid-describe-callback": "warn",
+        "vitest/valid-expect": "warn",
+        "typescript/no-non-null-asserted-optional-chain": "off"
+      }
+    }
+  ]
+}

.vscode/extensions.json

@@ -0,0 +1,3 @@
+{
+  "recommendations": ["oxc.oxc-vscode"]
+}

.vscode/settings.json

@@ -1,6 +1,7 @@
 {
-  "editor.defaultFormatter": "esbenp.prettier-vscode",
+  "editor.defaultFormatter": "oxc.oxc-vscode",
   "editor.formatOnSave": true,
+  "oxc.fmt.experimental": true,
   "search.exclude": {
     "**/node_modules": true,
     "**/.temp": true,

eng/pkg-pr-new.ts

@@ -1,5 +1,6 @@
 import { execSync } from "child_process";
 import { readdir } from "fs/promises";
+
 import { repoRoot } from "./utils/constants.ts";
 import { listChangedFilesSince } from "./utils/git.ts";
 

eng/prepare-release-pr.ts

@@ -1,3 +1,5 @@
+import { execSync } from "child_process";
+
 /* eslint-disable no-console */
 // @ts-check
 import { context, getOctokit } from "@actions/github";
@@ -6,7 +8,6 @@ import {
   renderReleasePlanAsMarkdown,
   resolveCurrentReleasePlan,
 } from "@chronus/chronus";
-import { execSync } from "child_process";
 const branchName = "publish/auto-release";
 
 const plan = await resolveCurrentReleasePlan(NodeChronusHost, process.cwd());

eng/sync-publish-config.ts

@@ -12,7 +12,9 @@
 //   node eng/sync-publish-config.ts --check    # exit non-zero if anything is stale
 /* eslint-disable no-console */
 import { existsSync, readdirSync, readFileSync, writeFileSync } from "fs";
+
 import { join } from "pathe";
+
 import { repoRoot } from "./utils/constants.ts";
 
 type Json = string | number | boolean | null | Json[] | { [key: string]: Json };
@@ -130,8 +132,8 @@ if (check && stale.length > 0) {
 
 if (!check) {
   console.log(
-    stale.length === 0 ?
-      "publishConfig already in sync."
-    : `Synced publishConfig for ${stale.length} package(s).`,
+    stale.length === 0
+      ? "publishConfig already in sync."
+      : `Synced publishConfig for ${stale.length} package(s).`,
   );
 }

package.json

@@ -16,29 +16,27 @@
     "test": "vitest run",
     "sync-publish-config": "node eng/sync-publish-config.ts",
     "sync-publish-config:check": "node eng/sync-publish-config.ts --check",
-    "format": "prettier . --write",
-    "format:check": "prettier . --check",
-    "lint": "eslint . --max-warnings=0",
-    "lint:fix": "eslint --fix ."
+    "format": "oxfmt",
+    "format:check": "oxfmt --check",
+    "lint": "oxlint --type-aware --disable-nested-config --max-warnings=0",
+    "lint:fix": "oxlint --type-aware --disable-nested-config --fix"
   },
   "devDependencies": {
     "@actions/github": "^9.1.1",
     "@alloy-js/cli": "workspace:~",
     "@chronus/chronus": "^1.1.0",
     "@chronus/github": "^1.0.3",
     "@chronus/github-pr-commenter": "^1.0.3",
-    "@eslint/js": "catalog:",
-    "@vitest/eslint-plugin": "catalog:",
+    "@types/node": "catalog:",
     "concurrently": "catalog:",
-    "eslint": "catalog:",
     "execa": "^9.6.0",
+    "oxfmt": "catalog:",
+    "oxlint": "catalog:",
+    "oxlint-tsgolint": "catalog:",
     "pathe": "^2.0.3",
-    "prettier": "catalog:",
-    "prettier-plugin-organize-imports": "catalog:",
     "rimraf": "catalog:",
     "tsx": "^4.20.3",
     "typedoc": "^0.28.8",
-    "typescript-eslint": "catalog:",
     "vitest": "catalog:"
   }
 }

packages/babel-plugin-alloy/src/index.ts

@@ -3,6 +3,7 @@ import PrinterMod from "@babel/generator/lib/printer.js";
 import SyntaxJSX from "@babel/plugin-syntax-jsx";
 import { NodePath } from "@babel/traverse";
 import * as t from "@babel/types";
+
 import { transformJSX } from "./transform.js";
 // when vite runs, PrinterMod is printer, otherwise PrinterMod.default is.
 // esm is so much fun.

packages/babel-plugin-alloy/test/basic.test.ts

@@ -1,6 +1,8 @@
-import { pluginTester } from "babel-plugin-tester";
 import { join } from "node:path";
+
+import { pluginTester } from "babel-plugin-tester";
 import "vitest";
+
 import plugin from "../src/index.js";
 
 pluginTester({

packages/babel-plugin-alloy/test/memo-naming.test.ts

@@ -1,5 +1,6 @@
-import { transformSync } from "@babel/core";
 import { join } from "node:path";
+
+import { transformSync } from "@babel/core";
 import { describe, expect, it } from "vitest";
 
 const pluginPath = join(

packages/cli/src/babel.ts

@@ -1,11 +1,12 @@
-import * as babel from "@babel/core";
+import { mkdir, writeFile } from "node:fs/promises";
+
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-expect-error
-import typescriptPreset from "@babel/preset-typescript";
+import alloyPreset from "@alloy-js/babel-preset";
+import * as babel from "@babel/core";
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-expect-error
-import alloyPreset from "@alloy-js/babel-preset";
-import { mkdir, writeFile } from "node:fs/promises";
+import typescriptPreset from "@babel/preset-typescript";
 import { basename, dirname, join, relative } from "pathe";
 
 export interface BuildOptions {

packages/cli/src/cli.ts

@@ -1,4 +1,5 @@
 import pc from "picocolors";
+
 import { buildCommand } from "./commands/build.js";
 import { installAgentsCommand } from "./commands/install-agents.js";
 import { installDocsCommand } from "./commands/install-docs.js";

packages/cli/src/commands/build.ts

@@ -1,7 +1,9 @@
 import { parseArgs } from "node:util";
+
 import { join } from "pathe";
 import pc from "picocolors";
 import ts from "typescript";
+
 import { buildAllFiles } from "../babel.js";
 import { getParseCommandLine } from "../typescript.js";