allow Gcf to destroy unknown managers

richardsheridan · richardsheridan · commit 7c48cbd1ffa5 · 2020-08-23T16:25:00.000-04:00
diff --git a/lib/matplotlib/_pylab_helpers.py b/lib/matplotlib/_pylab_helpers.py
@@ -53,18 +53,17 @@ def destroy(cls, num):
         It is recommended to pass a manager instance, to avoid confusion when
         two managers share the same number.
         """
-        if all(hasattr(num, attr) for attr in ["num", "_cidgcf", "destroy"]):
+        if all(hasattr(num, attr) for attr in ["num", "destroy"]):
             manager = num
             if cls.figs.get(manager.num) is manager:
                 cls.figs.pop(manager.num)
-            else:
-                return
         else:
             try:
                 manager = cls.figs.pop(num)
             except KeyError:
                 return
-        manager.canvas.mpl_disconnect(manager._cidgcf)
+        if hasattr(manager, "_cidgcf"):
+            manager.canvas.mpl_disconnect(manager._cidgcf)
         manager.destroy()
         gc.collect(1)
 
