chore: upgrade eslint config to flat config (#14)

* chore: upgrade eslint config to flat config

Migrates the config to be a flat config file (`eslint.config.js`).

To facilitate this, also updates a couple of packages:

- `typescript-eslint` (and drops the `@typescript-eslint/*` packages)
- prettier
- prettier ESLint config

We also removed `eslint-plugin-prettier` since the `format:check` script
achieves the same, and the ESLint config disables all stylistic rules.

* pnpm install

* demo.citty

* using void operator

---------

Co-authored-by: AmirSa12 <[email protected]>

Author: 43081j

.eslintrc.json

@@ -37,7 +37,7 @@ jobs:
         run: pnpm test
 
   typecheck:
-    name: Type Check
+    name: Lint and Type Check
     runs-on: ubuntu-latest
 
     steps:
@@ -57,5 +57,8 @@ jobs:
       - name: Install deps
         run: pnpm install
 
+      - name: Lint
+        run: pnpm lint
+
       - name: Type-check
         run: pnpm type-check

.github/workflows/ci.yml

@@ -1,4 +1,4 @@
-import { defineCommand, createMain, CommandDef } from 'citty';
+import { defineCommand, createMain, CommandDef, ArgsDef } from 'citty';
 import tab from './src/citty';
 
 const main = defineCommand({
@@ -58,7 +58,7 @@ const lintCommand = defineCommand({
 main.subCommands = {
   dev: devCommand,
   lint: lintCommand,
-} as Record<string, CommandDef<any>>;
+} as Record<string, CommandDef<ArgsDef>>;
 
 const completion = await tab(main, {
   subCommands: {
@@ -121,7 +121,7 @@ const completion = await tab(main, {
   },
 });
 
-completion;
+void completion;
 
 const cli = createMain(main);
 

demo.citty.ts

@@ -0,0 +1,19 @@
+import eslintjs from '@eslint/js';
+import { configs as tseslintConfigs } from 'typescript-eslint';
+import prettierConfig from 'eslint-config-prettier';
+
+const { configs: eslintConfigs } = eslintjs;
+
+export default [
+  {
+    ...eslintConfigs.recommended,
+    files: ['src/**/*.ts'],
+  },
+  ...tseslintConfigs.strict,
+  {
+    rules: {
+      '@typescript-eslint/no-unused-vars': 'off',
+    },
+  },
+  prettierConfig,
+];

eslint.config.js

@@ -11,7 +11,8 @@
     "format": "prettier --write .",
     "format:check": "prettier --check .",
     "build": "tsup",
-    "prepare": "pnpm build"
+    "prepare": "pnpm build",
+    "lint": "eslint src \"./*.ts\""
   },
   "files": [
     "dist"
@@ -21,15 +22,13 @@
   "license": "ISC",
   "devDependencies": {
     "@types/node": "^22.7.4",
-    "@typescript-eslint/eslint-plugin": "^8.20.0",
-    "@typescript-eslint/parser": "^8.20.0",
     "cac": "^6.7.14",
     "citty": "^0.1.6",
     "eslint-config-prettier": "^10.0.1",
-    "eslint-plugin-prettier": "^5.2.2",
-    "prettier": "^3.4.2",
+    "prettier": "^3.5.2",
     "tsup": "^8.3.6",
     "tsx": "^4.19.1",
+    "typescript-eslint": "^8.25.0",
     "typescript": "^5.7.3",
     "vitest": "^2.1.3"
   },