TEST: add test for adding color kwarg to scatter_matrix

Author: alexandercbooth

pandas/tests/plotting/test_misc.py

@@ -77,6 +77,10 @@ def scat(**kwds):
             _check_plot_works(scat, diagonal='hist')
         with tm.assert_produces_warning(UserWarning):
             _check_plot_works(scat, range_padding=.1)
+        with tm.assert_produces_warning(UserWarning):
+            _check_plot_works(scat, color='rgb')
+        with tm.assert_produces_warning(UserWarning):
+            _check_plot_works(scat, c='rgb')
 
         def scat2(x, y, by=None, ax=None, figsize=None):
             return plotting.scatter_plot(df, x, y, by, ax, figsize=None)