Add GitHub Actions testing, JSHint -> ESLint, rewrite tests in ESM

Also:
* switch to Node 20
* update dependencies

Author: mgol

.github/workflows/node.js.yml

@@ -0,0 +1,42 @@
+name: Node
+
+on:
+  pull_request:
+  push:
+    branches-ignore: ["dependabot/**"]
+
+permissions:
+  contents: read # to fetch code (actions/checkout)
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+    name: ${{ matrix.NPM_SCRIPT }} - ${{ matrix.NAME }} (${{ matrix.NODE_VERSION }})
+    strategy:
+      fail-fast: false
+      matrix:
+        NAME: ["Node"]
+        NODE_VERSION: [20.x]
+        NPM_SCRIPT: ["test"]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+
+      - name: Use Node.js ${{ matrix.NODE_VERSION }}
+        uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v4.0.2
+        with:
+          node-version: ${{ matrix.NODE_VERSION }}
+
+      - name: Cache
+        uses: actions/cache@ab5e6d0c87105b4c9c2047343972218f562e4319 # v4.0.1
+        with:
+          path: ~/.npm
+          key: ${{ runner.os }}-node-${{ matrix.NODE_VERSION }}-npm-lock-${{ hashFiles('**/package-lock.json') }}
+          restore-keys: |
+            ${{ runner.os }}-node-${{ matrix.NODE_VERSION }}-npm-lock-
+
+      - name: Install dependencies
+        run: npm install
+
+      - name: Run tests
+        run: npm test

.jshintrc

@@ -1 +1 @@
-10
+20

.nvmrc

@@ -0,0 +1,46 @@
+import jqueryConfig from "eslint-config-jquery";
+import globals from "globals";
+
+export default [
+	{
+		ignores: [
+			"test/fixtures/**"
+		]
+	},
+
+	{
+		languageOptions: {
+			globals: {
+				...globals.node
+			}
+		},
+		rules: {
+			...jqueryConfig.rules,
+			strict: [ "error", "global" ],
+
+			// Too many errors
+			"max-len": "off"
+		}
+	},
+
+	{
+		files: [
+			"test/*.js"
+		],
+		languageOptions: {
+			globals: {
+				...globals.node,
+				...globals.mocha
+			}
+		},
+		rules: {
+			...jqueryConfig.rules,
+
+			// Chai `expect` API violates this rule
+			"no-unused-expressions": "off",
+
+			// Too many errors
+			"max-len": "off"
+		}
+	}
+];

eslint.config.js

@@ -5,20 +5,20 @@ caches = [];
 
 cacheCron = function() {
 	var currentTime = Date.now();
-	caches.forEach(function( cache ) {
+	caches.forEach( function( cache ) {
 		var count = {
 			cached: 0,
 			deleted: 0
 		};
 
-		cache.each(function( value, key ) {
+		cache.each( function( _value, key ) {
 			count.cached++;
 			if ( cache.expires[ key ] < currentTime ) {
 				cache.destroy( key );
 				count.deleted++;
 			}
-		});
-	});
+		} );
+	} );
 	cacheCronTimeout = setTimeout( cacheCron, cacheExpiresTime );
 };
 

lib/cache.js

@@ -0,0 +1,3 @@
+{
+  "type": "commonjs"
+}