Change testing framework from Mocha to Jest (#719)

Also bumps node versions in CI from [12, 14, 16] to [14, 16, 18, 20].

Author: pradeepnschrodinger

Diff for: .github/workflows/build-and-run-tests.yml

@@ -18,7 +18,7 @@ jobs:
     # run this job for every combination of given matrix variables
     strategy:
       matrix:
-        node-version: [12.x, 14.x, 16.x]
+        node-version: [14.x, 16.x, 18.x, 20.x]
 
     steps:
 

Diff for: build_helpers/test-globals.js

@@ -0,0 +1,10 @@
+module.exports = {
+  moduleFileExtensions: ['js', 'jsx'],
+  moduleDirectories: ['node_modules'],
+
+  testRegex: ['.*-test.js'],
+
+  testEnvironment: 'jsdom',
+
+  setupFiles: ['<rootDir>/jest.setup.js'],
+};

Diff for: jest.config.js

@@ -0,0 +1,4 @@
+module.exports = async function () {
+  // NOTE (pradeep): Can this be synced with the definitions in webpack configs?
+  globalThis.__DEV__ = true;
+};

Diff for: jest.setup.js

@@ -36,8 +36,6 @@
     "@rollup/plugin-multi-entry": "^4.1.0",
     "@rollup/plugin-node-resolve": "^13.1.3",
     "@rollup/plugin-replace": "^4.0.0",
-    "@types/chai": "^4.2.10",
-    "@types/mocha": "^7.0.2",
     "@webpack-cli/serve": "^1.6.1",
     "aphrodite": "2.4.0",
     "autoprefixer": "^10.4.2",
@@ -46,7 +44,6 @@
     "babel-plugin-rewire": "1.2.0",
     "babel-plugin-syntax-trailing-function-commas": "^6.8.0",
     "bundle-loader": "0.5.6",
-    "chai": "4.2.0",
     "css-loader": "^5.2.7",
     "eslint": "7",
     "eslint-config-prettier": "6.10.0",
@@ -57,15 +54,13 @@
     "global": "^4.4.0",
     "html-loader": "0.5.5",
     "husky": "^4.2.3",
-    "jsdom": "^19.0.0",
+    "jest": "^29.7.0",
+    "jest-environment-jsdom": "^29.7.0",
     "less": "3.10.3",
     "less-loader": "5.0.0",
     "lint-staged": "^10.0.8",
     "marked": "4.0.10",
     "mini-css-extract-plugin": "^0.8.0",
-    "mocha": "^6.1.4",
-    "mocha-loader": "5.1.5",
-    "mocha-webpack": "2.0.0-beta.0",
     "null-loader": "3.0.0",
     "postcss": "^8.4.12",
     "postcss-custom-properties": "^12.1.4",
@@ -80,7 +75,6 @@
     "rollup": "^2.70.1",
     "rollup-plugin-postcss": "^4.0.2",
     "rollup-plugin-terser": "^7.0.2",
-    "sinon": "9.0.2",
     "style-loader": "1.0.0",
     "terser-webpack-plugin": "4.2.3",
     "url-loader": "2.1.0",
@@ -97,9 +91,8 @@
     "publish-site": "./build_helpers/publishStaticSite.sh",
     "publish-package": "./build_helpers/publishPackage.sh",
     "publish-beta": "./build_helpers/publishPackage.sh --beta",
-    "test": "mocha-webpack --webpack-config webpack.config-test.js \"test/**/*-test.js\" --require build_helpers/test-globals.js",
-    "test:watch": "mocha-webpack --webpack-config webpack.config-test.js --watch \"test/**/*-test.js\" --require build_helpers/test-globals.js",
-    "test:server": "webpack-dev-server --config webpack.config-test.js --hot"
+    "test": "jest",
+    "test:watch": "jest --watch"
   },
   "repository": {
     "type": "git",