chore: migrate to eslint v9

.github/workflows/test.yml

@@ -1,10 +1,10 @@
-name: build
+name: test
 on:
   workflow_dispatch:
   push:
     branches: [ main ]
 jobs:
-  build:
+  test:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3

README.md

@@ -27,7 +27,7 @@ operators do not use utils and I tried to avoid any internal dependency.
   package ESM only so `require` would fail to load the lib. The new flag
   `--experimental-require-module` can be used to load the lib if your app
   is in `commonjs` format. Checkout [the docs](https://nodejs.org/docs/latest/api/modules.html#loading-ecmascript-modules-using-require).
-* Add `tap` operator 
+* Add `tap` operator
 
 ### [0.4.0]
 

eslint.config.cjs

@@ -0,0 +1,48 @@
+const globals = require('globals');
+const eslintJs = require('@eslint/js');
+const prettierConfig = require('eslint-config-prettier');
+const prettierPlugin = require('eslint-plugin-prettier');
+
+module.exports = [
+  {
+    // This block should *only* have the "ignores" property.
+    // https://eslint.org/docs/latest/use/configure/configuration-files#globally-ignoring-files-with-ignores
+    ignores: ['node_modules/**', '.tap/**'],
+  },
+  {
+    languageOptions: {
+      ecmaVersion: 2022,
+      sourceType: 'module',
+      globals: {
+        ...globals.node,
+        fetch: false, // not present in node globals (readonly)
+      },
+      parserOptions: {
+        ecmaFeatures: {
+          jsx: true, // to parse nextjs files
+        },
+      },
+    },
+    plugins: {
+      prettier: prettierPlugin,
+    },
+    rules: {
+      ...eslintJs.configs.recommended.rules,
+      ...prettierConfig.rules,
+      'prettier/prettier': ['error'],
+      'prefer-arrow-callback': 'error',
+      'func-style': ['error', 'declaration', { allowArrowFunctions: true }],
+      'no-param-reassign': 'error',
+      'no-shadow': 'error',
+      'no-console': 'error',
+      'max-classes-per-file': 'error',
+      complexity: 'error',
+      'no-empty': 'error',
+      curly: 'error',
+      'max-len': ['error', { code: 132, comments: 162 }],
+      'max-lines': ['error', 1000],
+      quotes: ['error', 'single'],
+      'newline-per-chained-call': ['error', { ignoreChainWithDepth: 2 }],
+    },
+  },
+];