Add more tests for 80+% coverage

package.json

@@ -81,6 +81,8 @@
     "opn": "^5.1.0",
     "optimize-css-assets-webpack-plugin": "^3.2.0",
     "ora": "^1.1.0",
+    "phantomjs-polyfill": "^0.0.2",
+    "phantomjs-polyfill-find-index": "^1.0.1",
     "phantomjs-prebuilt": "^2.1.16",
     "rimraf": "^2.6.0",
     "sass-loader": "^6.0.3",
@@ -112,5 +114,8 @@
     "> 1%",
     "last 2 versions",
     "not ie <= 8"
-  ]
+  ],
+  "dependencies": {
+    "karma-polyfill": "^1.0.0"
+  }
 }