Working tests in Docker environment

* Install Chrome Headless during Docker build
* Use Chrome Headless if in a Docker environment (same configuration as
  in CI)

Author: outoftime

Dockerfile

@@ -1,5 +1,9 @@
 FROM node:8.10
 
+RUN wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | apt-key add -
+RUN sh -c 'echo "deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main" >> /etc/apt/sources.list.d/google.list'
+RUN apt-get update && apt-get install -y google-chrome-stable
+
 RUN echo '{"allow_root": true}' > /root/.bowerrc
 
 WORKDIR /app

karma.conf.js

@@ -2,6 +2,7 @@
 /* eslint-disable import/unambiguous */
 /* eslint-disable import/no-commonjs */
 
+const isDocker = require('is-docker');
 const webpackConfiguration = require('./webpack.config.js');
 
 const isCi = Boolean(process.env.TRAVIS);
@@ -76,7 +77,7 @@ module.exports = function(config) {
 
       reporters: ['dots', 'BrowserStack'],
     });
-  } else if (isCi) {
+  } else if (isCi || isDocker()) {
     config.set({
       browsers: ['ChromeHeadlessNoSandbox'],
       customLaunchers: {

package.json

@@ -268,6 +268,7 @@
     "immutable-devtools": "0.1.3",
     "imports-loader": "^0.8.0",
     "inline-chunk-manifest-html-webpack-plugin": "^2.0.0",
+    "is-docker": "^1.1.0",
     "json-loader": "^0.5.4",
     "karma": "^2.0.0",
     "karma-browserstack-launcher": "^1.1.1",

yarn.lock

@@ -5438,6 +5438,10 @@ is-directory@^0.3.1:
   version "0.3.1"
   resolved "https://registry.yarnpkg.com/is-directory/-/is-directory-0.3.1.tgz#61339b6f2475fc772fd9c9d83f5c8575dc154ae1"
 
+is-docker@^1.1.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/is-docker/-/is-docker-1.1.0.tgz#f04374d4eee5310e9a8e113bf1495411e46176a1"
+
 is-dotfile@^1.0.0:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/is-dotfile/-/is-dotfile-1.0.3.tgz#a6a2f32ffd2dfb04f5ca25ecd0f6b83cf798a1e1"