feat: use oxlint for faster lint

.vscode/extensions.json

@@ -3,6 +3,7 @@
         "svelte.svelte-vscode",
         "dbaeumer.vscode-eslint",
         "esbenp.prettier-vscode",
-        "vitest.explorer"
+        "vitest.explorer",
+        "oxc.oxc-vscode"
     ]
 }

.vscode/settings.json

@@ -21,6 +21,7 @@
     "javascript.preferences.importModuleSpecifier": "non-relative",
     "javascript.preferences.importModuleSpecifierEnding": "minimal",
     "typescript.preferences.importModuleSpecifierEnding": "minimal",
+    "oxc.typeAware": true,
     "vitest.nodeEnv": {
         // Enabling browser test on VSC vitest,
         // since it will not run browser tests by default

frontend/.oxlintrc.json

@@ -0,0 +1,63 @@
+{
+    "$schema": "./node_modules/oxlint/configuration_schema.json",
+    "plugins": [
+        "typescript",
+        "unicorn",
+        "import",
+        "vitest",
+        "promise"
+    ],
+    "jsPlugins": [
+        "eslint-plugin-phosphor-svelte"
+    ],
+    "env": {
+        "builtin": true
+    },
+    "ignorePatterns": [
+        "**/node_modules/**",
+        "**/dist/**",
+        "**/coverage/**",
+        "**/.cache/**",
+        "**/.vscode/**",
+        "**/.git/**",
+        "**/conductor/**"
+    ],
+    "overrides": [
+        {
+            "files": [
+                "**/*.d.ts"
+            ],
+            "rules": {
+                "no-unused-vars": "off"
+            }
+        },
+        {
+            "files": [
+                "**/*.svelte",
+                "**/*.svelte.ts"
+            ],
+            "rules": {
+                "prefer-const": "off",
+                "no-unassigned-vars": "off"
+            }
+        },
+        {
+            "files": [
+                "**/test/**",
+                "**/*.test.ts",
+                "**/*.test.tsx",
+                "**/*.spec.ts"
+            ],
+            "rules": {
+                "jest/require-to-throw-message": "off",
+                "jest/expect-expect": "off"
+            }
+        }
+    ],
+    "rules": {
+        "phosphor-svelte/optimize-imports": "warn"
+    },
+    "extends": [
+        "scripts/linter/oxlint-eslint.json"
+    ]
+}

frontend/common/logger/LogBridge.ts

@@ -1,5 +1,6 @@
+// oxlint-disable no-console
 // It's logger, so we should use console
-/* eslint-disable no-console */
+
 import type { StandardLogEntry, LogLevel, StructuredLogEntry } from "./Logger";
 import type { StructuredLogLevel } from "./LogType";
 

frontend/docs/rules/tools.md

@@ -0,0 +1,89 @@
+# Tools Configuration
+
+This document provides guidelines for configuring the linting and formatting tools in the ArisuTalk frontend project.
+
+## Linter Configuration
+
+This project uses **oxlint** as the primary linter for fast, type-aware linting, with **ESLint** as a fallback for rules that oxlint doesn't support yet.
+
+### Oxlint
+
+Fast linter for TypeScript and JavaScript, built on the Oxc compiler stack.
+
+**Supports:**
+
+- Most typescript-eslint rules, including type-aware rules
+- ESLint's JS plugins via the `jsPlugins` feature
+- Plugins: `typescript`, `unicorn`, `import`, `vitest`, `promise`
+
+**Doesn't support:**
+
+- Custom file formats and parsers (Svelte, Vue, Angular templates)
+- Some HTML-superset code (only checks `<script>` blocks in `.svelte` files)
+
+**Configuration:** `.oxlintrc.json` and `scripts/linter/`
+
+#### Adding New Plugins
+
+When using new ESLint plugins, try oxlint's [JS Plugins compatibility](https://oxc.rs/docs/guide/usage/linter/js-plugins.html) first:
+
+1. Add the plugin to `jsPlugins` in `.oxlintrc.json`:
+
+    ```json
+    {
+        "jsPlugins": ["eslint-plugin-foo"]
+    }
+    ```
+
+2. Add rules from the plugin under `rules`:
+
+    ```json
+    {
+        "rules": {
+            "foo/rule-name": "error"
+        }
+    }
+    ```
+
+3. If the plugin requires Svelte/Vue parser support, fall back to ESLint (see below).
+
+### ESLint
+
+ESLint is used **only** for rules that oxlint doesn't support, primarily:
+
+- Svelte template-specific rules (`eslint-plugin-svelte`)
+- Any future plugins requiring custom parsers
+
+**Configuration:** `eslint.config.js`
+
+The `eslint-plugin-oxlint` integration automatically disables ESLint rules that oxlint already handles, preventing duplicate warnings.
+
+### Running Linters
+
+```bash
+# Run oxlint only (fast, catches most issues)
+pnpm run lint:oxlint
+
+# Run ESLint only (Svelte template rules)
+pnpm run lint:eslint
+
+# Run both with auto-fix
+pnpm run lint
+
+# Run both without auto-fix (for CI)
+pnpm run lint:check
+```
+
+## Formatter Configuration
+
+This project uses **Prettier** for code formatting. Prettier is configured in `.prettierrc` and runs via:
+
+```bash
+# Format all files
+pnpm run format
+
+# Check formatting without modifying files
+pnpm run format:check
+```
+
+**Note:** `eslint-config-prettier` is **not** used, as CI already checks formatting separately and it can slow down TypeScript linting.

frontend/eslint.config.js

@@ -6,20 +6,19 @@ import { defineConfig } from "eslint/config";
 import { dirname } from "path";
 import { fileURLToPath } from "url";
 import phosphorSvelte from "eslint-plugin-phosphor-svelte";
+import oxlint from "eslint-plugin-oxlint";
 
 const __dirname = dirname(fileURLToPath(import.meta.url));
 
-const tsConfig = !process.env.SKIP_TYPE_LINT
-    ? ts.configs.recommendedTypeChecked
-    : ts.configs.recommended;
-
 const isCI = process.env.CI ? true : false;
+
 export default defineConfig([
     {
         ignores: ["dist/", "node_modules/", "*.config.*"],
     },
     js.configs.recommended,
-    ...tsConfig,
+    // No type check for it, oxlint does it.
+    ...ts.configs.recommended,
     ...svelte.configs["flat/recommended"],
     phosphorSvelte.configs.recommended,
     {
@@ -60,4 +59,8 @@ export default defineConfig([
             "no-console": "warn",
         },
     },
+    // Disable ESLint rules that are already handled by oxlint
+    ...oxlint.buildFromOxlintConfigFile(".oxlintrc.json", {
+        typeAware: true,
+    }),
 ]);

frontend/package.json

@@ -15,10 +15,12 @@
         "test:browser": "vitest run test/browser",
         "test:ui": "vitest --ui",
         "test:coverage": "vitest run test --coverage",
-        "check": "pnpm run format && pnpm run lint:fix && concurrently --group \"pnpm run test\" \"pnpm run test:browser\"",
+        "check": "pnpm run format && pnpm run lint && concurrently --group \"pnpm run test\" \"pnpm run test:browser\"",
         "check:types": "concurrently --group \"svelte-check --tsconfig tsconfig.app.json --fail-on-warnings\" \"svelte-check --tsconfig tsconfig.worker.json --fail-on-warnings\" \"svelte-check --tsconfig tsconfig.test.json\"",
-        "lint": "pnpm run check:types && eslint --cache --cache-location ./node_modules/.cache/eslint/ src/ test/ worker/ common/",
-        "lint:fix": "pnpm run lint --fix",
+        "lint:oxlint": "oxlint . --type-aware --type-check --report-unused-disable-directives-severity=off",
+        "lint:eslint": "eslint --cache --cache-location ./node_modules/.cache/eslint/ src/ test/ worker/ common/",
+        "lint": "pnpm run lint:oxlint --fix && pnpm run lint:eslint --fix",
+        "lint:check": "pnpm run check:types && pnpm run lint:oxlint && pnpm run lint:eslint",
         "format": "pnpm run format:check --write --list-different",
         "format:check": "prettier --cache --cache-location ./node_modules/.cache/prettier/ src/ test/ worker/"
     },
@@ -58,11 +60,14 @@
         "concurrently": "^9.2.1",
         "daisyui": "^5.5.13",
         "eslint": "^9.39.1",
+        "eslint-plugin-oxlint": "^1.48.0",
         "eslint-plugin-phosphor-svelte": "^0.0.2",
         "eslint-plugin-svelte": "^3.13.1",
         "fake-indexeddb": "^6.2.5",
         "globals": "^16.5.0",
         "happy-dom": "^20.0.10",
+        "oxlint": "^1.48.0",
+        "oxlint-tsgolint": "^0.14.0",
         "playwright": "^1.57.0",
         "postcss": "^8.5.6",
         "prettier": "^3.8.0",

frontend/scripts/linter/oxlint-eslint-error.json

@@ -0,0 +1,105 @@
+// Base rule, which is similar to ESLint. Machine-generated, unrecommended to edit manually.
+// Instead, extend this in .oxlintrc.json and override rules.
+{
+    "$schema": "../../node_modules/oxlint/configuration_schema.json",
+    "rules": {
+        "@typescript-eslint/await-thenable": "error",
+        "@typescript-eslint/ban-ts-comment": "error",
+        "@typescript-eslint/no-array-delete": "error",
+        "@typescript-eslint/no-base-to-string": "error",
+        "@typescript-eslint/no-duplicate-enum-values": "error",
+        "@typescript-eslint/no-duplicate-type-constituents": "error",
+        "@typescript-eslint/no-explicit-any": "error",
+        "@typescript-eslint/no-extra-non-null-assertion": "error",
+        "@typescript-eslint/no-floating-promises": "error",
+        "@typescript-eslint/no-for-in-array": "error",
+        "@typescript-eslint/no-implied-eval": "error",
+        "@typescript-eslint/no-misused-new": "error",
+        "@typescript-eslint/no-misused-promises": "error",
+        "@typescript-eslint/no-namespace": "error",
+        "@typescript-eslint/no-non-null-asserted-optional-chain": "error",
+        "@typescript-eslint/no-redundant-type-constituents": "error",
+        "@typescript-eslint/no-require-imports": "error",
+        "@typescript-eslint/no-this-alias": "error",
+        "@typescript-eslint/no-unnecessary-type-assertion": "error",
+        "@typescript-eslint/no-unnecessary-type-constraint": "error",
+        "@typescript-eslint/no-unsafe-argument": "error",
+        "@typescript-eslint/no-unsafe-assignment": "error",
+        "@typescript-eslint/no-unsafe-call": "error",
+        "@typescript-eslint/no-unsafe-declaration-merging": "error",
+        "@typescript-eslint/no-unsafe-enum-comparison": "error",
+        "@typescript-eslint/no-unsafe-function-type": "error",
+        "@typescript-eslint/no-unsafe-member-access": "error",
+        "@typescript-eslint/no-unsafe-return": "error",
+        "@typescript-eslint/no-unsafe-unary-minus": "error",
+        "@typescript-eslint/no-wrapper-object-types": "error",
+        "@typescript-eslint/only-throw-error": "error",
+        "@typescript-eslint/prefer-as-const": "error",
+        "@typescript-eslint/prefer-namespace-keyword": "error",
+        "@typescript-eslint/prefer-promise-reject-errors": "error",
+        "@typescript-eslint/restrict-plus-operands": "error",
+        "@typescript-eslint/restrict-template-expressions": "error",
+        "@typescript-eslint/triple-slash-reference": "error",
+        "constructor-super": "off",
+        "for-direction": "error",
+        "no-array-constructor": "error",
+        "no-async-promise-executor": "error",
+        "no-case-declarations": "error",
+        "no-class-assign": "off",
+        "no-compare-neg-zero": "error",
+        "no-cond-assign": "error",
+        "no-const-assign": "off",
+        "no-constant-binary-expression": "error",
+        "no-constant-condition": "error",
+        "no-control-regex": "error",
+        "no-debugger": "error",
+        "no-dupe-class-members": "off",
+        "no-dupe-else-if": "error",
+        "no-dupe-keys": "off",
+        "no-duplicate-case": "error",
+        "no-empty": "error",
+        "no-empty-character-class": "error",
+        "no-empty-pattern": "error",
+        "no-empty-static-block": "error",
+        "no-ex-assign": "error",
+        "no-extra-boolean-cast": "error",
+        "no-fallthrough": "error",
+        "no-func-assign": "off",
+        "no-import-assign": "off",
+        "no-invalid-regexp": "error",
+        "no-irregular-whitespace": "error",
+        "no-loss-of-precision": "error",
+        "no-misleading-character-class": "error",
+        "no-new-native-nonconstructor": "off",
+        "no-nonoctal-decimal-escape": "error",
+        "no-obj-calls": "off",
+        "no-prototype-builtins": "error",
+        "no-redeclare": "off",
+        "no-regex-spaces": "error",
+        "no-self-assign": "error",
+        "no-setter-return": "off",
+        "no-shadow-restricted-names": "error",
+        "no-sparse-arrays": "error",
+        "no-this-before-super": "off",
+        "no-unassigned-vars": "error",
+        "no-unsafe-finally": "error",
+        "no-unsafe-negation": "off",
+        "no-unsafe-optional-chaining": "error",
+        "no-unused-expressions": "error",
+        "no-unused-labels": "error",
+        "no-unused-private-class-members": "error",
+        "no-unused-vars": "error",
+        "no-useless-backreference": "error",
+        "no-useless-catch": "error",
+        "no-useless-escape": "error",
+        "no-var": "error",
+        "prefer-const": "error",
+        "prefer-rest-params": "error",
+        "prefer-spread": "error",
+        "preserve-caught-error": "error",
+        "require-yield": "error",
+        "use-isnan": "error",
+        "valid-typeof": "error"
+    },
+    "categories": {}
+}