diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index f333e761d5568ba256c3d5c48a2c6dfd6f4660b5..61ee1aff15b3aee0a869902a09b3bba73eaa676d 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -21,7 +21,7 @@ tests-and-coverage:
     - mkdir -p ~/.config/matplotlib
     - echo "backend:template" > ~/.config/matplotlib/matplotlibrc
     - mkdir public
-    - py.test -v -n $NUM_CORES --cov-report html --cov-report term --cov=. -m "not longrun" --html test-report/index.html --junitxml=report.xml
+    - py.test -v -n $NUM_CORES --cov-report html --cov-report xml --cov-report term --cov=. -m "not longrun" --html test-report/index.html --junitxml=report.xml
     - python3 -m coverage xml
   tags:
     - docker
diff --git a/doc/conf.py b/doc/conf.py
old mode 100644
new mode 100755
index c230cc945b3e58403af84146081aea79e83ca6c7..c493f806640eba010d1afee128b9bcd3ee5add3e
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -33,7 +33,7 @@ version = re.sub(r'(\d+\.\d+)\.\d+(.*)', r'\1\2', pystencils.__version__)
 version = re.sub(r'(\.dev\d+).*?$', r'\1', version)
 # The full version, including alpha/beta/rc tags.
 release = pystencils.__version__
-language = None
+language = 'en'
 exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store', '**.ipynb_checkpoints']
 default_role = 'any'
 pygments_style = 'sphinx'
diff --git a/pystencils/stencil.py b/pystencils/stencil.py
index 10925735a868a34297d566d4fa4e14736e727992..73ecb15713a54a5a5da3bbe68a8368699bb9145d 100644
--- a/pystencils/stencil.py
+++ b/pystencils/stencil.py
@@ -341,7 +341,7 @@ def plot_2d(stencil, axes=None, figure=None, data=None, textsize='12', **kwargs)
     for direction, annotation in zip(stencil, data):
         assert len(direction) == 2, "Works only for 2D stencils"
         direction = tuple(int(i) for i in direction)
-        if not(direction[0] == 0 and direction[1] == 0):
+        if not (direction[0] == 0 and direction[1] == 0):
             axes.arrow(0, 0, direction[0], direction[1], head_width=0.08, head_length=head_length, color='k')
 
         if isinstance(annotation, sp.Basic):