Merge pull request #7 from EOX-A/v2

feat!: convert to eslint flat config, include typescript

Author: silvester-pari

README.md

@@ -1,11 +1,33 @@
 # EOX ESLint & Prettier config for JS projects
+
+## About
+
+This reusable config aims to be our default way of setting up linting and formatting for JS projects. It includes:
+
+- eslint dependency
+- prettier dependency
+- typescript dependency
+- recommended eslint config
+- recommended typescript-eslint
+- typescript-eslint parser
+- vue-eslint parser
+- cypress rules
+- chai friendly errors
+
+The config also includes a minimal set of rules, defined in [index.js](./index.js).
+
 ## Installation
+
 ```js
 npm install --save-dev @eox/eslint-config
 ```
+
 ## Usage
+
 ### Prettier
+
 To run prettier and format all your files in the current folder, use
+
 ```bash
 npx prettier --write .
 or
@@ -15,23 +37,50 @@ npx prettier --write "**/*"
 Please refer to the [Prettier CLI docs](https://prettier.io/docs/en/cli.html) for further details.
 
 ### ESLint
-To include ESLint in the project, create a file called `.eslintrc.js` in the app root:
+
+To include ESLint in the project, create a file called `eslint.config.mjs` in the app root:
+
 ```js
-module.exports = {
-  extends: "@eox"
-}
+import eox from "@eox/eslint-config";
+
+export default [...eox];
 ```
+
 Finally, to run ESLint with auto-fixing, use
+
 ```bash
-npx eslint . --fix
+npx eslint --fix .
 ```
 
-Please refer to the [ESLint CLI docs](https://eslint.org/docs/latest/user-guide/command-line-interface) for further details.
+Please refer to the [ESLint configuration docs](https://eslint.org/docs/latest/use/configure/) and [ESLint CLI docs](https://eslint.org/docs/latest/user-guide/command-line-interface) for further details.
+
+### TypeScript
+
+To use typescript checks, create a `tsconfig.json` in the project root
+
+```json
+{
+  "compilerOptions": {
+    "allowJs": true,
+    "checkJs": true,
+    ...
+  }
+}
+```
+
+and run the check with
+
+```bash
+npx tsc
+```
 
 ## Ignoring files
-You can add [.eslintignore](https://eslint.org/docs/latest/user-guide/configuring/ignoring-code) and [.prettierignore](https://prettier.io/docs/en/ignore.html) files to ignore certain folders or files/patterns.
 
-Both ignore files should ideally have the same content, e.g.:
+not any longer -> only for prettier?
+
+You can add a [.prettierignore](https://prettier.io/docs/en/ignore.html) file to ignore certain folders or files/patterns.
+
+E.g.:
 
 ```
 public
@@ -42,32 +91,71 @@ dist
 # adapt according to your project needs
 ```
 
+For ESlint, use the [`ignores` property in the config file](https://eslint.org/docs/latest/use/configure/migration-guide#ignoring-files). Example:
+
+```js
+  // other config
+  { ignores: ["dist"] },
+  // other config
+```
+
 ## Custom configuration & rules
+
 Both Prettier and ESLint allow for some rule customization. Please check the [Prettier configuration options](https://prettier.io/docs/en/options.html) and the [ESLint rules](https://eslint.org/docs/rules/) for an explanation of rules that could be added/modified to this file for individual projects.
 
 BUT: please consider if this is really necessary, or if it could be included in the centralized config rather than in an individual project. Ideally, the individual projects should not use any custom rules.
 
+## Extend with plugins
+
+Example: Cypress & Vue
+
+```js
+// eslint.config.js
+import eox from "@eox/eslint-config";
+import pluginCypress from "eslint-plugin-cypress/flat";
+import pluginVue from "eslint-plugin-vue";
+
+export default [
+  ...eox,
+  pluginCypress.configs.recommended,
+  ...pluginVue.configs["flat/recommended"],
+  {
+    rules: {
+      // override/add rules settings here
+    },
+  },
+];
+```
+
 ## Checking for valid code
+
 To check if your code is valid before committing or inside a CI pipeline, use
+
 ```bash
 npx prettier --check .
 npx eslint .
 ```
 
 ## Automation in VS Code (extension, settings)
+
 ### Prettier
+
 Although you can use prettier via command line, in a pre-commit hook or in a CI pipeline, you can also use the VS Code extension to format files (or file sections) via a handy command or even automatically (e.g. on file save) right inside your code editor.
 
 --> [Prettier - Code formatter extension](https://marketplace.visualstudio.com/items?itemName=esbenp.prettier-vscode)
 
 Please refer to the description about setting up and using the extension!
 
 As a bare minimum, create a `.prettierrc.json` file in the app root to let the editor know prettier is used in this project
+
 ```js
 echo {} > .prettierrc.json
 ```
+
 ### ESLint
+
 As for ESLint, automatically running and fixing your code can be obtained by changing the settings in your workspace or dev container settings, e.g.:
+
 ```
 "editor.codeActionsOnSave": {
   "source.fixAll.eslint": true

index.js

@@ -1,14 +1,41 @@
-module.exports = {
-  root: true,
-  env: {
-    node: true,
-    browser: true
+import eslintConfigPrettier from "eslint-config-prettier";
+import globals from "globals";
+import eslint from "@eslint/js";
+import tseslint from "typescript-eslint";
+import tsParser from "@typescript-eslint/parser";
+import vueParser from "vue-eslint-parser";
+import pluginCypress from "eslint-plugin-cypress/flat";
+import pluginChaiFriendly from "eslint-plugin-chai-friendly";
+
+export default [
+  pluginCypress.configs.recommended,
+  eslint.configs.recommended,
+  ...tseslint.configs.recommended,
+  eslintConfigPrettier,
+  {
+    plugins: { "chai-friendly": pluginChaiFriendly },
+    languageOptions: {
+      parser: vueParser,
+      parserOptions: {
+        parser: tsParser,
+      },
+      globals: {
+        ...globals.node,
+        ...globals.browser,
+      },
+    },
+    rules: {
+      "@typescript-eslint/no-explicit-any": "warn",
+      "@typescript-eslint/no-unused-vars": [
+        "error",
+        {
+          varsIgnorePattern: "^_",
+          argsIgnorePattern: "^_",
+          caughtErrorsIgnorePattern: "^_",
+        },
+      ],
+      "@typescript-eslint/no-unused-expressions": "off", // disable original rule
+      "chai-friendly/no-unused-expressions": "error",
+    },
   },
-  extends: [
-    "eslint:recommended",
-    "plugin:vue/recommended",
-    "prettier"
-  ],
-  rules: {
-  },
-};
+];