Backport #13205 on branch v3.0.x (Add xvfb service to travis) (#13216)

NelleV · timhoffm · commit 4a63ccb99445 · 2019-01-19T09:28:19.000+01:00
* Add xvfb service to travis

* TST downgrading pytest

* CI: do not pull py35 test run back to trusty

This is to make sure we have the xvfb as a service
diff --git a/.appveyor.yml b/.appveyor.yml
@@ -66,7 +66,7 @@ install:
   - activate test-environment
   - echo %PYTHON_VERSION% %TARGET_ARCH%
   # pytest-cov>=2.3.1 due to https://github.com/pytest-dev/pytest-cov/issues/124
-  - pip install -q "pytest>=3.4" "pytest-cov>=2.3.1" pytest-rerunfailures pytest-timeout pytest-xdist
+  - pip install -q "pytest>=3.4,<4.0" "pytest-cov>=2.3.1" pytest-rerunfailures pytest-timeout pytest-xdist
 
   # Apply patch to `subprocess` on Python versions > 2 and < 3.6.3
   # https://github.com/matplotlib/matplotlib/issues/9176
diff --git a/.travis.yml b/.travis.yml
@@ -3,6 +3,9 @@ language: python
 dist: xenial
 sudo: false
 
+services:
+  - xvfb
+
 branches:
   except:
   - /^auto-backport-of-pr-\d*/
@@ -76,8 +79,6 @@ matrix:
         - RUN_FLAKE8=1
         - EXTRAREQS='-r requirements/testing/travis_flake8.txt'
     - python: 3.5
-      dist: trusty
-      # pytest-cov>=2.3.1 due to https://github.com/pytest-dev/pytest-cov/issues/124.
       env:
         - PINNEDVERS='-c requirements/testing/travis35.txt'
     - python: 3.6
@@ -156,10 +157,6 @@ install:
     python -mpip install -ve .
 
 before_script: |
-  if [[ $TRAVIS_OS_NAME != 'osx' ]]; then
-    export DISPLAY=:99.0
-    sh -e /etc/init.d/xvfb start
-  fi
   if [[ $DELETE_FONT_CACHE == 1 ]]; then
     rm -rf ~/.cache/matplotlib
   fi
diff --git a/requirements/testing/travis_all.txt b/requirements/testing/travis_all.txt
@@ -8,7 +8,7 @@ pillow
 pyparsing
 # pytest-timeout master depends on pytest>=3.6. Testing with pytest 3.4 is
 # still supported; this is tested by the first travis python 3.5 build
-pytest>=3.6
+pytest>=3.6,<4
 pytest-cov
 pytest-faulthandler
 pytest-rerunfailures
