COMPAT/BUG: color handling in scatter

MPL 1.5 seems to have changed the behavior of

ax.scatter(x, y, c='green', color=['blue'])

Since this doesn't really make sense anyway(?) I'm changing
our code so that the user doesn't get into that state.

Author: TomAugspurger

pandas/tests/test_graphics.py

@@ -2062,6 +2062,19 @@ def test_plot_scatter_with_c(self):
         float_array = np.array([0.0, 1.0])
         df.plot.scatter(x='A', y='B', c=float_array, cmap='spring')
 
+    def test_scatter_colors(self):
+        df = DataFrame({'a': [1, 2, 3], 'b': [1, 2, 3], 'c': [1, 2, 3]})
+        with tm.assertRaises(TypeError):
+            df.plot.scatter(x='a', y='b', c='c', color='green')
+
+        ax = df.plot.scatter(x='a', y='b', c='c')
+        tm.assert_numpy_array_equal(ax.collections[0].get_facecolor()[0],
+                                    (0, 0, 1, 1))
+
+        ax = df.plot.scatter(x='a', y='b', color='white')
+        tm.assert_numpy_array_equal(ax.collections[0].get_facecolor()[0],
+                                    (1, 1, 1, 1))
+
     @slow
     def test_plot_bar(self):
         df = DataFrame(randn(6, 4),

pandas/tools/plotting.py

@@ -1535,9 +1535,13 @@ def _make_plot(self):
         # pandas uses colormap, matplotlib uses cmap.
         cmap = self.colormap or 'Greys'
         cmap = self.plt.cm.get_cmap(cmap)
-
-        if c is None:
+        color = self.kwds.pop("color", None)
+        if c is not None and color is not None:
+            raise TypeError('Specify exactly one of `c` and `color`')
+        elif c is None and color is None:
             c_values = self.plt.rcParams['patch.facecolor']
+        elif color is not None:
+            c_values = color
         elif c_is_column:
             c_values = self.data[c].values
         else: