Make axisartist.axislines pseudo-tests real.

The results seem to be acceptable.
matplotlib · efiring · Feb 9, 2018 · Dec 1, 2016 · Dec 1, 2016 · Dec 1, 2016
commit bf25cf61ee57769bd69d9ced00b6fdb0922d127d
diff --git a/lib/mpl_toolkits/axisartist/axislines.py b/lib/mpl_toolkits/axisartist/axislines.py
@@ -826,48 +826,3 @@ def _init_axis_artists(self):
         self._axislines["yzero"] = yaxis_zero
 
 SubplotZero = maxes.subplot_class_factory(AxesZero)
-
-
-if 0:
-#if __name__ == "__main__":
-    import matplotlib.pyplot as plt
-
-    fig = plt.figure(1, (4,3))
-
-    ax = SubplotZero(fig, 1, 1, 1)
-    fig.add_subplot(ax)
-
-    ax.axis["xzero"].set_visible(True)
-    ax.axis["xzero"].label.set_text("Axis Zero")
-
-    for n in ["top", "right"]:
-        ax.axis[n].set_visible(False)
-
-    xx = np.arange(0, 2*np.pi, 0.01)
-    ax.plot(xx, np.sin(xx))
-    ax.set_ylabel("Test")
-    plt.draw()
-    plt.show()
-
-
-if __name__ == "__main__":
-#if 1:
-    import matplotlib.pyplot as plt
-
-    fig = plt.figure(1, (4,3))
-
-    ax = Subplot(fig, 1, 1, 1)
-    fig.add_subplot(ax)
-
-    xx = np.arange(0, 2*np.pi, 0.01)
-    ax.plot(xx, np.sin(xx))
-    ax.set_ylabel("Test")
-
-    ax.axis["top"].major_ticks.set_tick_out(True) #set_tick_direction("out")
-    ax.axis["bottom"].major_ticks.set_tick_out(True) #set_tick_direction("out")
-    #ax.axis["bottom"].set_tick_direction("in")
-
-    ax.axis["bottom"].set_label("Tk0")
-
-    plt.draw()
-    plt.show()
diff --git a/lib/mpl_toolkits/tests/baseline_images/test_axisartist_axislines/Subplot.png b/lib/mpl_toolkits/tests/baseline_images/test_axisartist_axislines/Subplot.png
diff --git a/lib/mpl_toolkits/tests/baseline_images/test_axisartist_axislines/SubplotZero.png b/lib/mpl_toolkits/tests/baseline_images/test_axisartist_axislines/SubplotZero.png
diff --git a/lib/mpl_toolkits/tests/test_axisartist_axislines.py b/lib/mpl_toolkits/tests/test_axisartist_axislines.py
@@ -0,0 +1,45 @@
+from __future__ import (absolute_import, division, print_function,
+                        unicode_literals)
+
+import numpy as np
+import matplotlib.pyplot as plt
+from matplotlib.testing.decorators import image_comparison
+
+from mpl_toolkits.axisartist.axislines import SubplotZero, Subplot
+
+
+@image_comparison(baseline_images=['SubplotZero'],
+                  extensions=['png'], style='default')
+def test_SubplotZero():
+    fig = plt.figure()
+
+    ax = SubplotZero(fig, 1, 1, 1)
+    fig.add_subplot(ax)
+
+    ax.axis["xzero"].set_visible(True)
+    ax.axis["xzero"].label.set_text("Axis Zero")
+
+    for n in ["top", "right"]:
+        ax.axis[n].set_visible(False)
+
+    xx = np.arange(0, 2 * np.pi, 0.01)
+    ax.plot(xx, np.sin(xx))
+    ax.set_ylabel("Test")
+
+
+@image_comparison(baseline_images=['Subplot'],
+                  extensions=['png'], style='default')
+def test_Subplot():
+    fig = plt.figure()
+
+    ax = Subplot(fig, 1, 1, 1)
+    fig.add_subplot(ax)
+
+    xx = np.arange(0, 2 * np.pi, 0.01)
+    ax.plot(xx, np.sin(xx))
+    ax.set_ylabel("Test")
+
+    ax.axis["top"].major_ticks.set_tick_out(True)
+    ax.axis["bottom"].major_ticks.set_tick_out(True)
+
+    ax.axis["bottom"].set_label("Tk0")