chore: switch to eslint flat config

eslint.config.js

@@ -0,0 +1,20 @@
+import eslintConfigESLint from "eslint-config-eslint";
+import globals from "globals";
+
+export default [
+    {
+        ignores: [
+            "coverage/",
+            "tests/fixtures/"
+        ]
+    },
+    ...eslintConfigESLint,
+    {
+        files: ["tests/**"],
+        languageOptions: {
+            globals: {
+                ...globals.mocha
+            }
+        }
+    }
+];

lib/init/config-file.js

@@ -64,7 +64,6 @@ async function writeYAMLConfigFile(config, filePath) {
     debug(`Writing YAML config file: ${filePath}`);
 
     // lazy load YAML to improve performance when not used
-    // eslint-disable-next-line node/no-unsupported-features/es-syntax
     const yaml = await import("js-yaml");
 
     const content = yaml.dump(config, { sortKeys: true });

lib/init/config-initializer.js

@@ -392,6 +392,7 @@ function askInstallModules(modules) {
 /**
  * Ask use a few questions on command prompt
  * @returns {Promise<void>} The promise with the result of the prompt
+ * @throws {Error} If `package.json` file doesn't exist.
  */
 function promptUser() {
     const packageJsonExists = npmUtils.checkPackageJson();
@@ -598,7 +599,8 @@ function promptUser() {
 }
 
 /* istanbul ignore next */
-/** an wrapper for promptUser
+/**
+ * an wrapper for promptUser
  *  @returns {void}
  */
 function initializeConfig() {

lib/init/npm-utils.js

@@ -52,8 +52,7 @@ function findPackageJson(startDir) {
 function installSyncSaveDev(packages, packageManager = "npm") {
     const packageList = Array.isArray(packages) ? packages : [packages];
     const installCmd = packageManager === "yarn" ? "add" : "install";
-    const installProcess = spawn.sync(packageManager, [installCmd, "-D"].concat(packageList),
-        { stdio: "inherit" });
+    const installProcess = spawn.sync(packageManager, [installCmd, "-D"].concat(packageList), { stdio: "inherit" });
     const error = installProcess.error;
 
     if (error && error.code === "ENOENT") {

package.json

@@ -29,7 +29,7 @@
         "access": "public"
     },
     "scripts": {
-        "lint": "eslint .",
+        "lint": "eslint . --report-unused-disable-directives",
         "release:generate:latest": "eslint-generate-release",
         "release:generate:alpha": "eslint-generate-prerelease alpha",
         "release:generate:beta": "eslint-generate-prerelease beta",
@@ -55,13 +55,12 @@
     "devDependencies": {
         "c8": "^7.10.0",
         "chai": "^4.3.4",
-        "eslint": "^8.2.0",
-        "eslint-config-eslint": "^7.0.0",
-        "eslint-plugin-jsdoc": "^37.0.3",
-        "eslint-plugin-node": "^11.1.0",
+        "eslint": "^8.48.0",
+        "eslint-config-eslint": "^9.0.0",
         "eslint-release": "^3.2.0",
         "esmock": "^2.2.3",
         "espree": "^9.0.0",
+        "globals": "^13.21.0",
         "lint-staged": "^12.1.2",
         "memfs": "^3.4.0",
         "mocha": "^9.1.3",

tests/init/config-file.js

@@ -66,7 +66,7 @@ describe("ConfigFile", () => {
 
             it(`should write a file through fs when a ${fileType} path is passed`, async () => {
                 const fakeFS = {
-                    writeFileSync: () => {}
+                    writeFileSync() {}
                 };
 
                 sinon.mock(fakeFS).expects("writeFileSync").withExactArgs(
@@ -84,7 +84,7 @@ describe("ConfigFile", () => {
 
             it("should include a newline character at EOF", async () => {
                 const fakeFS = {
-                    writeFileSync: () => {}
+                    writeFileSync() {}
                 };
 
                 sinon.mock(fakeFS).expects("writeFileSync").withExactArgs(
@@ -103,7 +103,7 @@ describe("ConfigFile", () => {
 
         it("should run 'eslint --fix' to make sure js config files match linting rules", async () => {
             const fakeFS = {
-                writeFileSync: () => {}
+                writeFileSync() {}
             };
 
             const singleQuoteConfig = {

tests/init/config-initializer.js

@@ -66,7 +66,7 @@ describe("configInitializer", () => {
 
     // copy into clean area so as not to get "infected" by this project's .eslintrc files
     before(() => {
-        const __filename = fileURLToPath(import.meta.url); // eslint-disable-line no-underscore-dangle
+        const __filename = fileURLToPath(import.meta.url); // eslint-disable-line no-underscore-dangle -- Conventional
 
         fixtureDir = path.join(__filename, "../../../tmp/eslint/fixtures/config-initializer");
         localInstalledEslintDir = path.join(fixtureDir, "./node_modules/eslint");