Switch to Chrome headless for Selenium test

.travis.yml

@@ -19,7 +19,6 @@ python:
 - '3.6'
 env:
   global:
-  - DISPLAY=:99.0
   - GECKO_DRIVER_VERSION=v0.16.1
   - CHROME_DRIVER_VERSION=2.29
   matrix:
@@ -42,12 +41,10 @@ matrix:
 install:
 - pip install --upgrade pip tox
 - pip install -U coveralls
-- sh -e /etc/init.d/xvfb start
 before_script:
 - mkdir bin
 - curl -O https://chromedriver.storage.googleapis.com/${CHROME_DRIVER_VERSION}/chromedriver_linux64.zip
 - unzip chromedriver_linux64.zip -d bin
-- curl -Lo - "https://github.com/mozilla/geckodriver/releases/download/${GECKO_DRIVER_VERSION}/geckodriver-${GECKO_DRIVER_VERSION}-linux64.tar.gz" | tar xzf - -C bin
 - PATH=$PATH:$PWD/bin
 - |
   if [[ -z $TOXENV ]]; then

tests/conftest.py

@@ -3,7 +3,6 @@
 
 import os
 import tempfile
-from time import sleep
 
 import pytest
 from django.core.files.base import ContentFile
@@ -17,22 +16,17 @@
 }
 
 
-@pytest.yield_fixture(scope='session', params=sorted(browsers.keys()))
-def driver(request):
-    if 'DISPLAY' not in os.environ:
-        pytest.skip('Test requires display server (export DISPLAY)')
-
+@pytest.yield_fixture(scope='session')
+def driver():
+    chrome_options = webdriver.ChromeOptions()
+    chrome_options.add_argument('headless')
+    chrome_options.add_argument('window-size=1200x800')
     try:
-        b = browsers[request.param]()
+        b = webdriver.Chrome(chrome_options=chrome_options)
     except WebDriverException as e:
         pytest.skip(force_text(e))
     else:
-        b.set_window_size(1200, 800)
-        b.implicitly_wait(0.1)
         yield b
-        if isinstance(b, webdriver.Chrome):
-            # chrome needs a couple of seconds before it can be quit
-            sleep(5)
         b.quit()