Move from eslint 8 to 9

* adapt to new config format
* moved test and react config into default config
* moved typescript-react config into typescript config
* removed `all`, `test`, `react` and `typescript-react` and separate configs

.github/workflows/run-tests.yml

@@ -7,7 +7,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [16.x, 18.x, 20.x]
+        node-version: [18.x, 20.x, 22.x]
 
     steps:
       - uses: actions/checkout@v2

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## 2.0.0
+
+- Breaking change: switch to eslint 8 to eslint 9 and adapt to the new flat file config format.
+- Breaking change: removed `all`, `react`, `test` and `typescript-react` configs. Replaced with the default config (js) and
+  just one for typescript `typescript` which includes react and test rules.
+
 ## 1.2.0
 
 - Bumped `typescript` to 5.4.3 and `@typescript-eslint` to 7.4.0.

README.md

@@ -15,71 +15,41 @@ Install `eslint` and `@bonniernews/eslint-config`:
 npm install --save-dev eslint @bonniernews/eslint-config
 ```
 
-### Base configuration
+## Migrating from 1.X to 2.X
 
-To activate the config, you need to add the following to your `.eslintrc.json`-file:
+2.X introduces eslint 9 which has a different configuration format. It is recommended to read the [eslint migration guide](https://eslint.org/docs/latest/use/configure/migration-guide).
 
-```json
-{
-  "root": true,
-  "extends": [ "@bonniernews" ]
-}
-```
+A major change from eslint 8 is that only one `eslint.config.js` file will be used, placing a specific configuration file in a folder will not behave in the same
+way as in 8 where it would inherit the configuration from files from the root folder, and the new recommendation is to just have one `eslint.config.js` at the root
+of the repository.
 
-### React configuration
+As well as changing the configuration format to adapt to eslint 9, @bonniernews/eslint-config has removed some of the previous configuration options `all`, `test`, `react`
+and `typescript-react` have all been removed. Now there are only two, the base (js only) and `typescript` which is the base with added support for `ts` and `tsx`.
 
-To activate the config, you need to add the following to your `.eslintrc.json`-file:
+### JavaScript configuration
 
-```json
-{
-  "root": true,
-  "extends": [ "@bonniernews/eslint-config/react" ]
-}
-```
+This config includes support for `js`, `jsx` and tests written using `mocha-cakes-2` and `chai`.
 
-This will enable the react plugin for `*.jsx`-files.
+To activate the config, you need to add the following to your `eslint.config.js`-file:
 
-### TypeScript configuration
-
-To activate the config, you need to add the following to your `.eslintrc.json`-file:
+```javascript
+"use strict";
 
-```json
-{
-  "root": true,
-  "extends": [ "@bonniernews/eslint-config/typescript" ]
-}
+module.exports = require("@bonniernews/eslint-config");
 ```
 
-This will enable the typescript plugin for `*.ts`-files.
+### TypeScript configuration
 
-### React with TypeScript configuration
+This config includes support for `js`, `jsx`, `ts`, `tsx` and and tests written using `mocha-cakes-2` and `chai`.
 
 To activate the config, you need to add the following to your `.eslintrc.json`-file:
 
-```json
-{
-  "root": true,
-  "extends": [ "@bonniernews/eslint-config/typescript-react" ]
-}
-```
-
-This will enable the typescript and react plugin for `*.tsx`-files.
+```javascript
+"use strict";
 
-### Test configuration
-
-You can also choose to use the test config, which is adapted to testing using `mocha`, `mocha-cakes-2` and `chai`. To also enable this,
-either add a separate test configuration file extending from `"@bonniernews/eslint-config/test"`, or use the `"@bonniernews/eslint-config/all"`
-in your root configuration to activate everything together:
-
-```json
-{
-  "root": true,
-  "extends": [ "@bonniernews/eslint-config/all" ]
-}
+module.exports = require("@bonniernews/eslint-config/typescript");
 ```
 
-This will activate the test configuration for all files inside directories named `test` or `tests`.
-
 ### Running eslint
 
 Run with:

base-config.js

@@ -0,0 +1,55 @@
+"use strict";
+
+const path = require("path");
+const fs = require("fs");
+const getRules = require("./rules");
+const globals = require("globals");
+
+const eslintPluginN = require("eslint-plugin-n");
+const eslintPluginImport = require("eslint-plugin-import");
+const eslintPluginTypescriptRules = require("@bonniernews/eslint-plugin-typescript-rules");
+
+// This will take care of potential symlinks
+const appDir = fs.realpathSync(process.cwd());
+
+const isModuleProject = require(path.resolve(appDir, "package.json")).type === "module";
+const hasES2022Support = parseInt(process.versions.node.split(".").shift(), 10) >= 16;
+
+const moduleConfig = {
+  languageOptions: {
+    ecmaVersion: hasES2022Support ? 2022 : 2021,
+    globals: { ...globals.node },
+    sourceType: "module",
+  },
+  plugins: {
+    n: eslintPluginN,
+    import: eslintPluginImport,
+    "@bonniernews/typescript-rules": eslintPluginTypescriptRules,
+  },
+};
+
+const commonjsConfig = {
+  languageOptions: {
+    ecmaVersion: 2021,
+    sourceType: "commonjs",
+    globals: { ...globals.node },
+  },
+  plugins: {
+    n: eslintPluginN,
+    "@bonniernews/typescript-rules": eslintPluginTypescriptRules,
+  },
+};
+
+const baseConfig = {
+  ignores: [
+    "tmp/",
+    "public/",
+    "submodule/**",
+    "logs/",
+    "docs/",
+  ],
+  ...(isModuleProject ? moduleConfig : commonjsConfig),
+  rules: getRules(isModuleProject),
+};
+
+module.exports = baseConfig;

eslint.config.js

@@ -0,0 +1,6 @@
+"use strict";
+
+module.exports = [
+  { ignores: [ "test/data/**/*" ] },
+  ...require("./index.js"),
+];

index.js

@@ -1,44 +1,27 @@
 "use strict";
 
-const path = require("path");
-const fs = require("fs");
-const getRules = require("./rules");
+const reactPlugin = require("eslint-plugin-react");
+const reactRules = require("./react-rules");
+const baseConfig = require("./base-config");
+const testConfig = require("./test");
 
-// This will take care of potential symlinks
-const appDir = fs.realpathSync(process.cwd());
-
-const isModuleProject = require(path.resolve(appDir, "package.json")).type === "module";
-const hasES2022Support = parseInt(process.versions.node.split(".").shift(), 10) >= 16;
-
-const moduleConfig = {
-  parserOptions: {
-    ecmaVersion: hasES2022Support ? 2022 : 2021,
-    sourceType: "module",
+module.exports = [
+  baseConfig,
+  {
+    ...baseConfig,
+    files: [ "**/*.jsx" ],
+    languageOptions: {
+      ...baseConfig.languageOptions,
+      parserOptions: { ecmaFeatures: { jsx: true } },
+    },
+    plugins: { ...baseConfig.plugins, react: reactPlugin },
+    rules: { ...baseConfig.rules, ...reactRules },
   },
-  env: {
-    node: true,
-    ...(hasES2022Support ? { es2022: true } : { es6: true }),
+  {
+    ...baseConfig,
+    languageOptions: { ...baseConfig.languageOptions, ...testConfig.languageOptions },
+    plugins: { ...baseConfig.plugins, ...testConfig.plugins },
+    rules: { ...baseConfig.rules, ...testConfig.rules },
+    files: [ "test/**/*.js" ],
   },
-  plugins: [ "eslint-plugin-n", "import", "@bonniernews/typescript-rules" ],
-};
-
-const commonjsConfig = {
-  parserOptions: { ecmaVersion: 2021 },
-  env: {
-    node: true,
-    es6: true,
-  },
-  plugins: [ "eslint-plugin-n", "@bonniernews/typescript-rules" ],
-};
-
-module.exports = {
-  ignorePatterns: [
-    "tmp/",
-    "public/",
-    "submodule/**",
-    "logs/",
-    "docs/",
-  ],
-  ...(isModuleProject ? moduleConfig : commonjsConfig),
-  rules: getRules(isModuleProject),
-};
+];