Test browsers directly on Travis

Travis provides some browsers at least, so let's test those directly
without having to go through Sauce Labs.

.travis.yml

@@ -7,17 +7,17 @@ node_js:
   - lts/*
 env:
   matrix:
-  - TEST_BROWSER_NAME=chrome TEST_BROWSER_OS='Windows 10'
+  - USE_SAUCE=1 TEST_BROWSER_NAME=chrome TEST_BROWSER_OS='Windows 10'
 # FIXME Skip tests in Linux since Sauce Labs browser versions are ancient.
-#  - TEST_BROWSER_NAME=chrome TEST_BROWSER_OS='Linux'
+#  - USE_SAUCE=1 TEST_BROWSER_NAME=chrome TEST_BROWSER_OS='Linux'
-  - TEST_BROWSER_NAME=chrome TEST_BROWSER_OS='OS X 10.11'
+  - USE_SAUCE=1 TEST_BROWSER_NAME=chrome TEST_BROWSER_OS='OS X 10.11'
-  - TEST_BROWSER_NAME=firefox TEST_BROWSER_OS='Windows 10'
+  - USE_SAUCE=1 TEST_BROWSER_NAME=firefox TEST_BROWSER_OS='Windows 10'
-#  - TEST_BROWSER_NAME=firefox TEST_BROWSER_OS='Linux'
+#  - USE_SAUCE=1 TEST_BROWSER_NAME=firefox TEST_BROWSER_OS='Linux'
-  - TEST_BROWSER_NAME=firefox TEST_BROWSER_OS='OS X 10.11'
+  - USE_SAUCE=1 TEST_BROWSER_NAME=firefox TEST_BROWSER_OS='OS X 10.11'
-  - TEST_BROWSER_NAME='internet explorer' TEST_BROWSER_OS='Windows 10'
+  - USE_SAUCE=1 TEST_BROWSER_NAME='internet explorer' TEST_BROWSER_OS='Windows 10'
-  - TEST_BROWSER_NAME='internet explorer' TEST_BROWSER_OS='Windows 7'
+  - USE_SAUCE=1 TEST_BROWSER_NAME='internet explorer' TEST_BROWSER_OS='Windows 7'
-  - TEST_BROWSER_NAME=microsoftedge TEST_BROWSER_OS='Windows 10'
+  - USE_SAUCE=1 TEST_BROWSER_NAME=microsoftedge TEST_BROWSER_OS='Windows 10'
-  - TEST_BROWSER_NAME=safari TEST_BROWSER_OS='OS X 10.13'
+  - USE_SAUCE=1 TEST_BROWSER_NAME=safari TEST_BROWSER_OS='OS X 10.13'
 before_script: npm install -g karma-cli
 addons:
   sauce_connect:
@@ -41,6 +41,29 @@ jobs:
     addons:
     before_script:
     script: git ls-tree --name-only -r HEAD | grep -E "[.](html|css)$" | xargs ./utils/validate
+  - stage: test
+    env:
+    - TEST_BROWSER_NAME=FirefoxHeadless
+    addons:
+      sauce_connect: false
+    before_script:
+    script: npm run test
+  -
+    env:
+    - TEST_BROWSER_NAME=ChromeHeadless
+    addons:
+      sauce_connect: false
+      chrome: stable
+    before_script:
+    script: npm run test
+  -
+    os: osx
+    env:
+    - TEST_BROWSER_NAME=Safari
+    addons:
+      sauce_connect: false
+    before_script:
+    script: npm run test
   - stage: deploy
     env:
     addons:

karma.conf.js

@@ -5,12 +5,11 @@ module.exports = (config) => {
   let browsers = [];
   let useSauce = false;
 
-  // use Sauce when running on Travis
+  if (process.env.USE_SAUCE) {
-  if (process.env.TRAVIS_JOB_NUMBER) {
     useSauce = true;
   } 
 
-  if (useSauce && process.env.TEST_BROWSER_NAME && process.env.TEST_BROWSER_NAME != 'PhantomJS') {
+  if (useSauce) {
     const names = process.env.TEST_BROWSER_NAME.split(',');
     const platforms = process.env.TEST_BROWSER_OS.split(',');
     const versions = process.env.TEST_BROWSER_VERSION
@@ -40,9 +39,9 @@ module.exports = (config) => {
 
     browsers = Object.keys(customLaunchers);
   } else {
-    useSauce = false;
+    if (process.env.TEST_BROWSER_NAME) {
-    //browsers = ['PhantomJS'];
+      browsers = process.env.TEST_BROWSER_NAME.split(',');
-    browsers = [];
+    }
   }
 
   const my_conf = {

package.json

@@ -60,8 +60,11 @@
     "jsdom": "*",
     "karma": "*",
     "karma-mocha": "*",
+    "karma-chrome-launcher": "*",
+    "karma-firefox-launcher": "*",
     "karma-mocha-reporter": "*",
     "karma-sauce-launcher": "*",
+    "karma-safari-launcher": "*",
     "karma-sinon-chai": "*",
     "mocha": "*",
     "node-getopt": "*",