migrate eslint to v9

Author: mshr-h

.eslintrc.json

@@ -0,0 +1,48 @@
+import { defineConfig, globalIgnores } from "eslint/config";
+import typescriptEslint from "@typescript-eslint/eslint-plugin";
+import tsParser from "@typescript-eslint/parser";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+import js from "@eslint/js";
+import { FlatCompat } from "@eslint/eslintrc";
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+const compat = new FlatCompat({
+    baseDirectory: __dirname,
+    recommendedConfig: js.configs.recommended,
+    allConfig: js.configs.all
+});
+
+export default defineConfig([globalIgnores([
+    "**/out",
+    "**/dist",
+    "**/*.d.ts",
+    "src/bsvjs/syntaxes",
+    "src/test",
+    "src/BsvProvider.ts",
+]), {
+    extends: compat.extends("eslint:recommended", "prettier"),
+
+    plugins: {
+        "@typescript-eslint": typescriptEslint,
+    },
+
+    languageOptions: {
+        parser: tsParser,
+        ecmaVersion: 6,
+        sourceType: "module",
+    },
+
+    rules: {
+        "@typescript-eslint/naming-convention": "warn",
+        "@/semi": "warn",
+        curly: "warn",
+        eqeqeq: "warn",
+        "no-throw-literal": "warn",
+        semi: "off",
+        "no-unused-vars": "off",
+        "no-undef": "warn",
+        "no-constant-condition": "warn",
+    },
+}]);