chore: use ESLint's flat config

.ls-lint.yml

@@ -7,5 +7,6 @@ ignore:
   - dist
   - node_modules
   - rollup.config.js
+  - eslint.config.js
   - karma.conf.js
   - benchmarks

eslint.config.js

@@ -0,0 +1,47 @@
+import babelParser from '@babel/eslint-parser';
+import js from '@eslint/js';
+import chaiExpect from 'eslint-plugin-chai-expect';
+import chaiFriendly from 'eslint-plugin-chai-friendly';
+import simpleImportSort from 'eslint-plugin-simple-import-sort';
+import globals from 'globals';
+
+export default [
+  {
+    files: ['**/*.mjs', '**/*.js'],
+    ignores: ['src/parser/parser.mjs'],
+    languageOptions: {
+      ecmaVersion: 2023,
+      parser: babelParser,
+      sourceType: 'module',
+    },
+    plugins: {
+      'simple-import-sort': simpleImportSort,
+    },
+    rules: {
+      ...js.configs.recommended.rules,
+      'padding-line-between-statements': [
+        'error',
+        { blankLine: 'never', prev: '*', next: 'case' },
+        { blankLine: 'never', prev: '*', next: 'default' },
+        { blankLine: 'always', prev: 'block-like', next: 'break' },
+      ],
+      'simple-import-sort/imports': 'error',
+    },
+  },
+  {
+    files: ['src/**/__tests__/*.test.mjs'],
+    languageOptions: {
+      globals: globals.mocha,
+    },
+    plugins: {
+      'chai-expect': chaiExpect,
+      'chai-friendly': chaiFriendly,
+    },
+    rules: {
+      'no-unused-expressions': 0,
+      'sort-keys': 'off',
+      ...chaiExpect.configs.recommended.rules,
+      'chai-friendly/no-unused-expressions': 2,
+    },
+  },
+];