pytest xfail needs a 'reason'

pizzathief · pizzathief · commit b0a342d7ed05 · 2016-01-21T12:09:06.000+11:00
diff --git a/lib/matplotlib/tests/test_colors.py b/lib/matplotlib/tests/test_colors.py
@@ -398,7 +398,8 @@ def test_light_source_shading_default():
 
 
 @pytest.mark.xfail((V(np.__version__) <= V('1.9.0')
-                and V(np.__version__) >= V('1.7.0')))
+                and V(np.__version__) >= V('1.7.0')),
+                reason='numpy version needs to be between 1.7 and 1.9')
 # Numpy 1.9.1 fixed a bug in masked arrays which resulted in
 # additional elements being masked when calculating the gradient thus
 # the output is different with earlier numpy versions.
diff --git a/lib/matplotlib/tests/test_mlab.py b/lib/matplotlib/tests/test_mlab.py
@@ -2751,7 +2751,8 @@ def get_z(x, y):
                                   np.ma.getmask(correct_zi_masked))
 
 
-@pytest.mark.xfail(not HAS_NATGRID)
+@pytest.mark.xfail(not HAS_NATGRID, 
+                   reason='import of the natgrid toolkit failed')
 def test_griddata_nn():
     # z is a linear function of x and y.
     def get_z(x, y):
