Add a test based on @pelson's example in #1591.

mdboom · mdboom · commit 8fe199ba8fdd · 2013-03-01T14:28:00.000-05:00
diff --git a/lib/matplotlib/tests/test_image.py b/lib/matplotlib/tests/test_image.py
@@ -195,6 +195,37 @@ def test_image_shift():
               extent=(tMin, tMax, 1, 100))
     ax.set_aspect('auto')
 
+@cleanup
+def test_image_edges():
+    f = plt.figure(figsize=[1, 1])
+    ax = f.add_axes([0, 0, 1, 1], frameon=False)
+
+    data = np.tile(np.arange(12), 15).reshape(20, 9)
+
+    im = ax.imshow(data, origin='upper',
+                   extent=[-10, 10, -10, 10], interpolation='none',
+                   cmap='gray'
+                   )
+
+    x = y = 2
+    ax.set_xlim([-x, x])
+    ax.set_ylim([-y, y])
+
+    ax.set_xticks([])
+    ax.set_yticks([])
+
+    buf = io.BytesIO()
+    f.savefig(buf, facecolor=(0, 1, 0))
+
+    buf.seek(0)
+
+    im = plt.imread(buf)
+    r, g, b, a = sum(im[:, 0])
+    r, g, b, a = sum(im[:, -1])
+
+    assert g != 100, 'Expected a non-green edge - but sadly, it was.'
+
+
 if __name__=='__main__':
     import nose
     nose.runmodule(argv=['-s','--with-doctest'], exit=False)
