update js dependencies, move to jest for testing (#5821)

* update js dependencies, move to jest for testing

This commit updates the js dependencies to the latest versions and moves
from mocha to jest for testing. This is consistent with the setup we
use in LiveView.

* run npm tests on node 20

.github/workflows/ci.yml

@@ -85,10 +85,10 @@ jobs:
           restore-keys: |
             deps-${{ runner.os }}-npm
 
-      - name: Set up Node.js 12.x
+      - name: Set up Node.js 20.x
         uses: actions/setup-node@v4
         with:
-          node-version: 12.x
+          node-version: 20.x
 
       - name: Restore npm cache
         uses: actions/cache@v4

assets/.eslintrc.js

@@ -2,17 +2,18 @@ module.exports = {
     "env": {
         "browser": true,
         "es2021": true,
+        "jest/globals": true
+    },
+    "extends": "eslint:recommended",
+    "globals": {
+        "global": "writable"
     },
-    "extends": [
-        "eslint:recommended",
-        "plugin:mocha/recommended"
-    ],
     "parserOptions": {
         "ecmaVersion": 12,
         "sourceType": "module"
     },
     "plugins": [
-        "mocha"
+        "jest"
     ],
     "rules": {
         "indent": [
@@ -75,8 +76,6 @@ module.exports = {
         ],
         "no-useless-escape": "off",
         "no-cond-assign": "off",
-        "no-case-declarations": "off",
-        "mocha/no-skipped-tests": "off",
-        "mocha/max-top-level-suites": "off"
+        "no-case-declarations": "off"
     }
-}
+}

assets/.gitignore

@@ -0,0 +1 @@
+/coverage/

assets/jest.config.js

@@ -0,0 +1,27 @@
+/*
+ * For a detailed explanation regarding each configuration property, visit:
+ * https://jestjs.io/docs/configuration
+ */
+
+module.exports = {
+  // Automatically clear mock calls and instances between every test
+  clearMocks: true,
+
+  // Indicates which provider should be used to instrument code for coverage
+  coverageProvider: "v8",
+
+  // The paths to modules that run some code to configure or set up the testing environment before each test
+  setupFiles: [
+    // "<rootDir>/setupTests.js"
+  ],
+
+  // The test environment that will be used for testing
+  testEnvironment: "jest-environment-jsdom-global",
+
+  testEnvironmentOptions: {
+    url: "https://example.com"
+  },
+
+  // The regexp pattern or array of patterns that Jest uses to detect test files
+  testRegex: "/test/.*_test\\.js$",
+};

assets/js/phoenix/socket.js

@@ -376,7 +376,7 @@ export default class Socket {
 
     errorRef = this.onError(reason => {
       this.log("transport", "error", reason)
-      if(primaryTransport && !established) {
+      if(primaryTransport && !established){
         clearTimeout(this.fallbackTimer)
         fallback(reason)
       }