Improve test for invalid rotated inputs

Author: deep-jkl

lib/matplotlib/markers.py

@@ -456,7 +456,7 @@ def rotated(self, deg=None, rad=None):
 
         .. note:: You must specify exactly one of deg or rad.
         """
-        if not ((deg is None) ^ (rad is None)):
+        if not (deg is None) ^ (rad is None):
             raise ValueError("Exactly one of deg or rad shall be used.")
 
         new_marker = MarkerStyle(self)

lib/matplotlib/tests/test_marker.py

@@ -229,6 +229,7 @@ def test_marker_rotated_invalid():
     marker = markers.MarkerStyle("o")
     with pytest.raises(ValueError):
         new_marker = marker.rotated()
+    with pytest.raises(ValueError):    
         new_marker = marker.rotated(deg=10, rad=10)