Make edgecolors and facecolors the same when using stepfilled histogram.

Closes matplotlib#6493

lib/matplotlib/axes/_axes.py

@@ -6292,8 +6292,8 @@ def _normalize_input(inp, ename='input'):
                         facecolor=c,
                         margins=margins))
             else:
-                for x, y, c in reversed(list(zip(xvals, yvals, color))):
-                    split = 2 * len(bins)
+                split = 2 * len(bins)
+                for x, y, c in reversed(list(zip(xvals, yvals, reversed(color)))):
                     patches.append(self.fill(
                         x[:split], y[:split],
                         closed=False, edgecolor=c,

lib/matplotlib/tests/test_axes.py

@@ -1150,6 +1150,16 @@ def test_hist_steplog():
     ax = plt.subplot(4, 1, 4)
     plt.hist(data_big, 100, histtype='stepfilled', log=True, orientation='horizontal')
 
+@image_comparison(baseline_images=['hist_step_filled'], extensions=['png'])
+def test_hist_step_empty():
+    import numpy as np
+    import matplotlib.pyplot as plt
+    x = np.random.randn(1000, 3)
+    fig, ax = plt.subplots()
+    ax.hist(x, n_bins,  histtype='step', fill=True, stacked=True)
+    patches= ax.patches
+    all([p.get_facecolor() == p.get_edgecolor() for p in patches])
+
 
 @image_comparison(baseline_images=['hist_step_log_bottom'],
                   remove_text=True, extensions=['png'])