Stop transpiling karma tests

This runs our code in the same manner as it would be used if loaded
directly in the browser. Includes the same kind of fallback for older
browsers.

karma.conf.js

@@ -4,7 +4,6 @@ module.exports = (config) => {
   const customLaunchers = {};
   let browsers = [];
   let useSauce = false;
-  let transpileToES5 = ['internet explorer'].includes(process.env.TEST_BROWSER_NAME);
 
   // use Sauce when running on Travis
   if (process.env.TRAVIS_JOB_NUMBER) {
@@ -53,7 +52,7 @@ module.exports = (config) => {
 
     // frameworks to use
     // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
-    frameworks: ['requirejs', 'mocha', 'sinon-chai'],
+    frameworks: ['mocha', 'sinon-chai'],
 
     // list of files / patterns to load in the browser (loaded in order)
     files: [
@@ -61,9 +60,11 @@ module.exports = (config) => {
       { pattern: 'app/webutil.js', included: false },
       { pattern: 'core/**/*.js', included: false },
       { pattern: 'vendor/pako/**/*.js', included: false },
+      { pattern: 'vendor/browser-es-module-loader/dist/*.js*', included: false },
       { pattern: 'tests/test.*.js', included: false },
       { pattern: 'tests/fake.*.js', included: false },
       { pattern: 'tests/assertions.js', included: false },
+      'vendor/promise.js',
       'tests/karma-test-main.js',
     ],
 
@@ -85,26 +86,6 @@ module.exports = (config) => {
     // available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
     browsers: browsers,
 
-    // preprocess matching files before serving them to the browser
-    // available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
-    preprocessors: {
-      'app/localization.js': ['babel'],
-      'app/webutil.js': ['babel'],
-      'core/**/*.js': ['babel'],
-      'tests/test.*.js': ['babel'],
-      'tests/fake.*.js': ['babel'],
-      'tests/assertions.js': ['babel'],
-      'vendor/pako/**/*.js': ['babel'],
-    },
-
-    babelPreprocessor: {
-      options: {
-        presets: transpileToES5 ? ['es2015'] : [],
-        plugins: ['transform-es2015-modules-amd', 'syntax-dynamic-import'],
-        sourceMap: 'inline',
-      },
-    },
-
     // test results reporter to use
     // possible values: 'dots', 'progress'
     // available reporters: https://npmjs.org/browse/keyword/karma-reporter

package.json

@@ -46,10 +46,8 @@
     "fs-extra": "^1.0.0",
     "jsdom": "*",
     "karma": "^1.3.0",
-    "karma-babel-preprocessor": "^6.0.1",
     "karma-mocha": "^1.3.0",
     "karma-mocha-reporter": "^2.2.0",
-    "karma-requirejs": "^1.1.0",
     "karma-sauce-launcher": "^1.0.0",
     "karma-sinon-chai": "^2.0.0",
     "mocha": "^3.1.2",

tests/karma-test-main.js

@@ -9,8 +9,39 @@ Object.keys(window.__karma__.files).forEach(function (file) {
     }
 });
 
-require.config({
-    baseUrl: '/base',
-    deps: allTestFiles.concat(extraFiles),
-    callback: window.__karma__.start,
+// Stub out mocha's start function so we can run it once we're done loading
+mocha.origRun = mocha.run;
+mocha.run = function () {};
+
+let script;
+
+// Script to import all our tests
+script = document.createElement("script");
+script.type = "module";
+script.text = "";
+let allModules = allTestFiles.concat(extraFiles);
+allModules.forEach(function (file) {
+    script.text += "import \"" + file + "\";\n";
 });
+script.text += "\nmocha.origRun();\n";
+document.body.appendChild(script);
+
+// Fallback code for browsers that don't support modules (IE)
+script = document.createElement("script");
+script.type = "module";
+script.text = "window._noVNC_has_module_support = true;\n";
+document.body.appendChild(script);
+
+function fallback() {
+    if (!window._noVNC_has_module_support) {
+        /* eslint-disable no-console */
+        if (console)
+            console.log("No module support detected. Loading fallback...");
+        /* eslint-enable no-console */
+        let loader = document.createElement("script");
+        loader.src = "base/vendor/browser-es-module-loader/dist/browser-es-module-loader.js";
+        document.body.appendChild(loader);
+    }
+}
+
+setTimeout(fallback, 500);