chore: update to eslint 9 (#2204)

Author: KTibow

.eslintrc.json

@@ -0,0 +1,129 @@
+import { defineConfig } from "eslint/config";
+import globals from "globals";
+import js from "@eslint/js";
+import n from "eslint-plugin-n";
+import unicorn from "eslint-plugin-unicorn";
+import tseslint from "typescript-eslint";
+import eslintConfigPrettier from "eslint-config-prettier";
+
+export default defineConfig([
+    js.configs.recommended,
+    n.configs["flat/recommended"],
+    unicorn.configs.recommended,
+    tseslint.configs.recommended,
+    eslintConfigPrettier,
+    {
+        languageOptions: {
+            globals: {
+                ...globals.node,
+            },
+        },
+
+        rules: {
+            eqeqeq: [2, "smart"],
+            "no-caller": 2,
+            "dot-notation": 2,
+            "no-var": 2,
+            "prefer-const": 2,
+
+            "prefer-arrow-callback": [
+                2,
+                {
+                    allowNamedFunctions: true,
+                },
+            ],
+
+            "arrow-body-style": [2, "as-needed"],
+            "object-shorthand": 2,
+            "prefer-template": 2,
+            "one-var": [2, "never"],
+
+            "prefer-destructuring": [
+                2,
+                {
+                    object: true,
+                },
+            ],
+
+            "capitalized-comments": 2,
+            "multiline-comment-style": [2, "starred-block"],
+            "spaced-comment": 2,
+            yoda: [2, "never"],
+            curly: [2, "multi-line"],
+            "no-else-return": 2,
+            "n/no-unpublished-import": 0,
+
+            "unicorn/filename-case": [
+                2,
+                {
+                    cases: {
+                        camelCase: true,
+                        pascalCase: true,
+                    },
+                },
+            ],
+
+            "unicorn/no-null": 0,
+            "unicorn/prefer-code-point": 0,
+            "unicorn/prefer-string-slice": 0,
+            "unicorn/prefer-add-event-listener": 0,
+            "unicorn/prefer-at": 0,
+            "unicorn/prefer-string-replace-all": 0,
+        },
+    },
+    {
+        files: ["**/*.ts"],
+
+        languageOptions: {
+            sourceType: "module",
+            parser: tseslint.parser,
+
+            parserOptions: {
+                project: "./tsconfig.json",
+            },
+        },
+
+        rules: {
+            curly: [2, "multi-line"],
+            "@typescript-eslint/prefer-for-of": 0,
+            "@typescript-eslint/member-ordering": 0,
+            "@typescript-eslint/explicit-function-return-type": 0,
+            "@typescript-eslint/no-unused-vars": 0,
+
+            "@typescript-eslint/no-use-before-define": [
+                2,
+                {
+                    functions: false,
+                },
+            ],
+
+            "@typescript-eslint/consistent-type-definitions": [2, "interface"],
+            "@typescript-eslint/prefer-function-type": 2,
+            "@typescript-eslint/no-unnecessary-type-arguments": 2,
+            "@typescript-eslint/prefer-string-starts-ends-with": 2,
+            "@typescript-eslint/prefer-readonly": 2,
+            "@typescript-eslint/prefer-includes": 2,
+            "@typescript-eslint/no-unnecessary-condition": 2,
+            "@typescript-eslint/switch-exhaustiveness-check": 2,
+            "@typescript-eslint/prefer-nullish-coalescing": 2,
+
+            "@typescript-eslint/consistent-type-imports": [
+                2,
+                {
+                    fixStyle: "inline-type-imports",
+                },
+            ],
+
+            "@typescript-eslint/consistent-type-exports": 2,
+            "n/no-missing-import": 0,
+            "n/no-unsupported-features/es-syntax": 0,
+        },
+    },
+    {
+        files: ["**/*.spec.ts"],
+
+        rules: {
+            "n/no-unsupported-features/node-builtins": 0,
+        },
+    },
+]);