Eslint v9 & flat configs (#1397)

* Chore: migrate to eslint@9

* Chore: eslint unicorn

.github/workflows/main.yml

@@ -14,6 +14,8 @@ jobs:
           node-version: 20
           cache: 'yarn'
       - run: yarn install --immutable --immutable-cache
+      - name: Typescript
+        run: yarn turbo tsc
       - name: Eslint
         run: yarn eslint .
       - name: Validate package setup

eslint.config.js

@@ -0,0 +1,73 @@
+// @ts-check
+import eslint from '@eslint/js';
+import globals from 'globals';
+import tseslint from 'typescript-eslint';
+import nodePlugin from 'eslint-plugin-n';
+import eslintPluginPrettierRecommended from 'eslint-plugin-prettier/recommended';
+import eslintPluginUnicorn from 'eslint-plugin-unicorn';
+
+export default tseslint.config(
+  {
+    ignores: [
+      '.git',
+      'node_modules',
+      'coverage',
+      'packages/*/dist/**',
+      'packages/*/node_modules/**',
+      'packages/*/__snapshots__/**',
+    ],
+  },
+  eslint.configs.recommended,
+  nodePlugin.configs['flat/recommended-module'],
+  eslintPluginUnicorn.configs['flat/recommended'],
+  {
+    languageOptions: {
+      globals: {
+        ...globals.nodeBuiltin,
+      },
+    },
+    rules: {
+      'unicorn/consistent-function-scoping': 'off',
+      'unicorn/filename-case': 'off',
+      'unicorn/no-array-callback-reference': 'off',
+      'unicorn/no-array-for-each': 'off',
+      'unicorn/no-array-reduce': 'off',
+      'unicorn/no-null': 'off',
+      'unicorn/no-process-exit': 'off',
+      'unicorn/prefer-event-target': 'off',
+      'unicorn/prefer-top-level-await': 'off',
+      'unicorn/prevent-abbreviations': 'off',
+    },
+  },
+  {
+    files: ['**/*.mts', '**/*.ts'],
+    extends: [...tseslint.configs.recommended],
+  },
+  {
+    files: ['**/*.cjs'],
+    extends: [nodePlugin.configs['flat/recommended-script']],
+    languageOptions: {
+      globals: {
+        ...globals.node,
+      },
+    },
+  },
+  {
+    files: ['packages/inquirer/test/**', 'packages/**/*.test.*'],
+    rules: {
+      'n/no-extraneous-import': [
+        'error',
+        {
+          allowModules: ['vitest'],
+        },
+      ],
+      'n/no-extraneous-require': [
+        'error',
+        {
+          allowModules: ['vitest'],
+        },
+      ],
+    },
+  },
+  eslintPluginPrettierRecommended,
+);

package.json

@@ -48,19 +48,17 @@
   ],
   "devDependencies": {
     "@arethetypeswrong/cli": "^0.15.3",
+    "@eslint/js": "^9.1.1",
     "@sindresorhus/tsconfig": "^5.0.0",
     "@types/node": "^20.12.7",
-    "@typescript-eslint/eslint-plugin": "^7.7.1",
-    "@typescript-eslint/parser": "^7.7.1",
     "@vitest/coverage-v8": "^1.5.2",
     "@vitest/ui": "^1.5.2",
-    "eslint": "^8.57.0",
+    "eslint": "^9.1.1",
     "eslint-config-prettier": "^9.1.0",
-    "eslint-config-xo": "^0.44.0",
-    "eslint-plugin-import": "^2.29.1",
     "eslint-plugin-n": "^17.3.1",
     "eslint-plugin-prettier": "^5.1.3",
     "eslint-plugin-unicorn": "^52.0.0",
+    "globals": "^15.0.0",
     "globby": "^14.0.1",
     "husky": "^9.0.11",
     "lerna": "^8.1.2",
@@ -69,6 +67,7 @@
     "ts-node": "^10.9.2",
     "turbo": "^1.13.3",
     "typescript": "^5.4.5",
+    "typescript-eslint": "^7.7.1",
     "vitest": "^1.5.2"
   },
   "resolutions": {

packages/checkbox/src/index.mts

@@ -247,4 +247,4 @@ export default createPrompt(
   },
 );
 
-export { Separator };
+export { Separator } from '@inquirer/core';

packages/core/src/lib/create-prompt.mts

@@ -47,8 +47,8 @@ export function createPrompt<Value, Config>(view: ViewFunction<Value, Config>) {
             store.hooksCleanup.forEach((cleanFn) => {
               cleanFn?.();
             });
-          } catch (err) {
-            reject(err);
+          } catch (error) {
+            reject(error);
           }
 
           if (context?.clearPromptOnDone) {
@@ -89,9 +89,9 @@ export function createPrompt<Value, Config>(view: ViewFunction<Value, Config>) {
             screen.render(content, bottomContent);
 
             effectScheduler.run();
-          } catch (err) {
+          } catch (error) {
             onExit();
-            reject(err);
+            reject(error);
           }
         }
 

packages/core/src/lib/use-state.mts

@@ -1,5 +1,6 @@
 import { withPointer, handleChange } from './hook-engine.mjs';
 
+// eslint-disable-next-line @typescript-eslint/ban-types
 type NotFunction<T> = T extends Function ? never : T;
 
 export function useState<Value>(

packages/demo/demos/input.mjs

@@ -2,7 +2,7 @@ import * as url from 'node:url';
 import chalk from 'chalk';
 import { input } from '@inquirer/prompts';
 
-const hexRegEx = /([0-9]|[a-f])/gim;
+const hexRegEx = /(\d|[a-f])/gim;
 const isHex = (value) =>
   (value.match(hexRegEx) || []).length === value.length &&
   (value.length === 3 || value.length === 6);

packages/editor/editor.test.mts

@@ -75,12 +75,15 @@ describe('editor prompt', () => {
       message: 'Add a description',
       validate(value) {
         switch (value) {
-          case '1':
+          case '1': {
             return true;
-          case '2':
+          }
+          case '2': {
             return '"2" is not an allowed value';
-          default:
+          }
+          default: {
             return false;
+          }
         }
       },
     });

packages/inquirer/examples/filter-validate-progress.js

@@ -4,8 +4,6 @@
 
 import inquirer from '../lib/inquirer.js';
 
-/* eslint-disable no-promise-executor-return */
-
 const questions = [
   {
     type: 'input',

packages/inquirer/examples/long-list.js

@@ -5,20 +5,22 @@
 import inquirer from '../lib/inquirer.js';
 
 const choices = Array.apply(0, Array.from({ length: 26 })).map((x, y) =>
-  String.fromCharCode(y + 65),
+  String.fromCodePoint(y + 65),
+);
+choices.push(
+  'Multiline option 1\n  super cool feature \n  more lines',
+  'Multiline option 2\n  super cool feature \n  more lines',
+  'Multiline option 3\n  super cool feature \n  more lines',
+  'Multiline option 4\n  super cool feature \n  more lines',
+  'Multiline option 5\n  super cool feature \n  more lines',
+  new inquirer.Separator(),
+  'Multiline option \n  super cool feature',
+  {
+    name: 'Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Donec quam felis, ultricies nec, pellentesque eu, pretium quis, sem. Nulla consequat massa quis enim. Donec pede justo, fringilla vel, aliquet nec, vulputate eget, arcu. In enim justo, rhoncus ut, imperdiet a, venenatis vitae, justo. Nullam dictum felis eu pede mollis pretium.',
+    value: 'foo',
+    short: 'The long option',
+  },
 );
-choices.push('Multiline option 1\n  super cool feature \n  more lines');
-choices.push('Multiline option 2\n  super cool feature \n  more lines');
-choices.push('Multiline option 3\n  super cool feature \n  more lines');
-choices.push('Multiline option 4\n  super cool feature \n  more lines');
-choices.push('Multiline option 5\n  super cool feature \n  more lines');
-choices.push(new inquirer.Separator());
-choices.push('Multiline option \n  super cool feature');
-choices.push({
-  name: 'Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Donec quam felis, ultricies nec, pellentesque eu, pretium quis, sem. Nulla consequat massa quis enim. Donec pede justo, fringilla vel, aliquet nec, vulputate eget, arcu. In enim justo, rhoncus ut, imperdiet a, venenatis vitae, justo. Nullam dictum felis eu pede mollis pretium.',
-  value: 'foo',
-  short: 'The long option',
-});
 
 inquirer
   .prompt([

packages/inquirer/examples/regex-validate-input.js

@@ -14,7 +14,7 @@ const questions = [
         return true;
       }
 
-      throw Error('Please provide a valid API key secret.');
+      throw new Error('Please provide a valid API key secret.');
     },
   },
 ];

packages/inquirer/examples/rx-observable-array.js

@@ -36,10 +36,10 @@ const observable = from(questions);
 
 inquirer.prompt(observable).ui.process.subscribe(
   (ans) => {
-    console.log('Answer is: ', ans);
+    console.log('Answer is:', ans);
   },
   (err) => {
-    console.log('Error: ', err);
+    console.log('Error:', err);
   },
   () => {
     console.log('Completed');

packages/inquirer/lib/objects/choice.js

@@ -10,7 +10,6 @@ export default class Choice {
   constructor(val, answers) {
     // Don't process Choice and Separator object
     if (val instanceof Choice || val.type === 'separator') {
-      // eslint-disable-next-line no-constructor-return
       return val;
     }
 

packages/inquirer/lib/prompts/base.js

@@ -104,10 +104,10 @@ export default class Prompt {
             this.startSpinner(filteredValue, this.opt.validatingText);
             return validate(filteredValue, this.answers).then(
               (isValid) => ({ isValid, value: filteredValue }),
-              (err) => ({ isValid: err, value: filteredValue }),
+              (error_) => ({ isValid: error_, value: filteredValue }),
             );
           },
-          (err) => ({ isValid: err }),
+          (error_) => ({ isValid: error_ }),
         );
       }),
       share(),

packages/inquirer/lib/prompts/list.js

@@ -60,7 +60,7 @@ export default class ListPrompt extends Base {
         take(1),
         map(this.getCurrentValue.bind(this)),
         flatMap((value) =>
-          runAsync(this.opt.filter)(value, this.answers).catch((err) => err),
+          runAsync(this.opt.filter)(value, this.answers).catch((error) => error),
         ),
       )
       .forEach(this.onSubmit.bind(this));

packages/inquirer/lib/utils/events.js

@@ -4,7 +4,7 @@ function normalizeKeypressEvents(value, key) {
   return { value, key: key || {} };
 }
 
-export default function (rl) {
+export default function observe(rl) {
   const keypress = fromEvent(rl.input, 'keypress', normalizeKeypressEvents)
     .pipe(takeUntil(fromEvent(rl, 'close')))
     // Ignore `enter` key. On the readline, we only care about the `line` event.