Install libs before running tests on qt

.travis.yml

@@ -1,26 +1,41 @@
-dist: xenial
+dist: bionic
 language: python
 branches:
   only:
     - master
 
+sudo: required
+
+before_install:
+  - sudo apt-get update
+  - sudo apt-get install -y xvfb herbstluftwm
+
+install:
+  - "export DISPLAY=:99.0"
+  - "/sbin/start-stop-daemon --start --quiet --pidfile /tmp/custom_xvfb_99.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :99 -screen 0 1920x1200x24 -ac +extension GLX +render -noreset"
+  - sleep 3
+  - pip install tox
+
 matrix:
   include:
     - python: 3.8
       env: TOXENV=flake8
     - python: 3.8
       env: TOXENV=black
-    - python: 3.8
-      env: TOXENV=mypy
     - python: 3.6
       env: TOXENV=py36
     - python: 3.7
       env: TOXENV=py37
     - python: 3.8
       env: TOXENV=py38
+    - python: 3.6
+      env: TOXENV=codecov
+    - python: 3.6
+      env: TOXENV=check_packaging
 
-install:
-  - pip install tox
+before_script:
+  - "herbstluftwm &"
+  - sleep 1
 
 script:
   - tox

requirements_tests.txt

@@ -5,4 +5,5 @@ pre-commit
 pytest
 pytest-cov
 pytest-qt
+pytest-xvfb
 tox

tox.ini

@@ -2,29 +2,25 @@
 envlist = py36, py37, py38, black, packaging, codecov
 
 [default]
-
 basepython = python3.8
 
 [testenv]
+passenv = DISPLAY XAUTHORITY
 setenv =
     PYTHONPATH = {toxinidir}
-
-commands = pytest --cov-append --cov=nodedge tests/
+commands = pytest -s -vv --cov-append --cov=nodedge
 deps =
     -rrequirements.txt
     -rrequirements_tests.txt
 
 [testenv:black]
-
 description = run Black (linter)
 basepython = {[default]basepython}
 skip_install = True
-
 commands =
     black {env:BLACK_LINT_ARGS:} nodedge
 
 [testenv:flake8]
-
 description = run Flake8 (linter)
 basepython = {[default]basepython}
 skip_install = True
@@ -38,14 +34,11 @@ max-line-length = 89
 max-complexity = 18
 select = B,C,E,F,W,T4,B9
 
-[testenv:packaging]
+[testenv:check_packaging]
 
 description = check for potential packaging problems
-
 basepython = {[default]basepython}
-
 skip_install = True
-
 deps =
    check-manifest==0.40
    readme_renderer==24.0