test subplots use symmetric, transitive share.

lkjell · lkjell · commit c9a585d1033d · 2018-03-10T00:37:18.000+01:00
diff --git a/lib/matplotlib/tests/test_subplots.py b/lib/matplotlib/tests/test_subplots.py
@@ -19,8 +19,12 @@ def check_shared(axs, x_shared, y_shared):
             enumerate(zip("xy", [x_shared, y_shared]))):
         if i2 <= i1:
             continue
-        share = getattr(ax2, "_shared_{}_axes".format(name))
-        share = ax1 in share
+        # symmetric share
+        shareA = getattr(ax1, "_shared_{}_axes".format(name))
+        shareA = ax2 in shareA
+        shareB = getattr(ax2, "_shared_{}_axes".format(name))
+        shareB = ax1 in shareB
+        share = shareA and shareB
         assert \
             (share
              == shared[i1, i2]), \
