made it work in IE11 because Array.from

Author: spacerockzero

.babelrc

@@ -0,0 +1,10 @@
+{
+  "presets": [
+    ["env", {
+      "targets": {
+        "browsers": ["last 2 versions"],
+        "uglify": true
+      }
+    }]
+  ]
+}

gulpfile.js

@@ -1,35 +1,45 @@
 const gulp = require('gulp');
-const sourcemaps = require('gulp-sourcemaps');
+// const sourcemaps = require('gulp-sourcemaps');
 const browserify = require('browserify');
 const source = require('vinyl-source-stream');
 const buffer = require('vinyl-buffer');
 const uglify = require('gulp-uglify');
 const watchify = require('watchify');
 const babel = require('babelify');
-const es2015 = require('babel-preset-es2015');
+// const env = require('babel-preset-env');
 const postcss = require('gulp-postcss');
 const autoprefixer = require('autoprefixer');
 const cssnano = require('cssnano');
 const svgo = require('gulp-svgo');
 const sass = require('gulp-sass');
 const livereload = require('gulp-livereload');
 
-function conf() {
-  const opts = {};
-  opts.builtins = false;
-  opts.entries = ['src/js/index.js'];
-  opts.debug = true;
-  opts.insertGlobalVars = {
+// function conf() {
+//   const opts = {};
+//   opts.builtins = false;
+//   opts.entries = ['src/js/index.js'];
+//   opts.debug = true;
+//   opts.insertGlobalVars = {
+//     global: glob
+//   };
+//   return opts;
+// }
+const opts = {
+  builtins: false,
+  entries: ['src/js/index.js'],
+  debug: true,
+  insertGlobalVars: {
     global: glob
-  };
-  return opts;
-}
+  }
+};
 
 const uglifyConf = {};
 
 function compile(watch) {
-  const opts = conf();
-  const bundler = watchify(browserify(opts).transform([babel, es2015]));
+  // const opts = conf();
+  const bundler = watchify(browserify(opts).transform(babel.configure({
+    presets: ['env']
+  })));
   function rebundle() {
     return bundler.bundle()
       .on('error', err => {
@@ -38,11 +48,11 @@ function compile(watch) {
       })
       .pipe(source('bundle.min.js'))
       .pipe(buffer())
-      .pipe(sourcemaps.init({
-        loadMaps: true
-      }))
+      // .pipe(sourcemaps.init({
+      //   loadMaps: true
+      // }))
       .pipe(uglify(uglifyConf))
-      .pipe(sourcemaps.write('./'))
+      // .pipe(sourcemaps.write('./'))
       .pipe(gulp.dest('./public/dist/js'));
   }
   if (watch) {

package.json

@@ -43,7 +43,6 @@
     "babelify": "^7.3.0",
     "cssnano": "^3.10.0",
     "gulp": "^3.9.1",
-    "gulp-bro": "^1.0.2",
     "gulp-postcss": "^6.4.0",
     "gulp-sourcemaps": "^2.5.1",
     "gulp-uglify": "^2.1.2",
@@ -57,6 +56,7 @@
     "xo": "^0.18.1"
   },
   "devDependencies": {
+    "babel-preset-env": "^1.4.0",
     "babel-preset-es2017": "^6.24.1",
     "babel-preset-latest": "^6.24.1",
     "browserify": "^14.1.0",

public/dist/js/bundle.min.js

@@ -204,7 +204,7 @@
         allPassed = false;
       }
     });
-    const testEls = Array.from(testSuiteEl.querySelectorAll('.test-state'));
+    const testEls = Array.prototype.slice.call(testSuiteEl.querySelectorAll('.test-state'));
     testEls.forEach((testStatusEl, iter) => {
       if (testStatuses[iter] === true) {
         testStatusEl.innerHTML = '[✓]';
@@ -330,10 +330,10 @@
     function problemNav(e) {
       // Go to previous problem keybinding
       // If CMD/CTRL + SHIFT + RETURN/ENTER
-      if (config.shuffle === false && e.keyCode === 13 && e.shiftKey && e.metaKey) {
+      if (config.shuffle === false && e.keyCode === 13 && e.shiftKey && (e.metaKey || e.ctrlKey)) {
         // Go to next problem
         previousProblem();
-      } else if (e.keyCode === 13 && !e.shiftKey && e.metaKey) {
+      } else if (e.keyCode === 13 && !e.shiftKey && (e.metaKey || e.ctrlKey)) {
       // Go to next problem keybinding
       // If CMD/CTRL + RETURN/ENTER
         // Go to next problem