matplotlib · timhoffm · Mar 19, 2020 · Mar 18, 2020
diff --git a/lib/matplotlib/_pylab_helpers.py b/lib/matplotlib/_pylab_helpers.py
@@ -45,14 +45,23 @@ def get_fig_manager(cls, num):
     @classmethod
     def destroy(cls, num):
         """
-        Destroy figure number *num*.
+        Destroy manager *num* -- either a manager instance or a manager number.
 
         In the interactive backends, this is bound to the window "destroy" and
         "delete" events.
+
+        It is recommended to pass a manager instance, to avoid confusion when
+        two managers share the same number.
         """
-        if not cls.has_fignum(num):
-            return
-        manager = cls.figs.pop(num)
+        if all(hasattr(num, attr) for attr in ["num", "_cidgcf", "destroy"]):
+            manager = num
+            if cls.figs.get(manager.num) is manager:
+                cls.figs.pop(manager.num)
+        else:
+            try:
+                manager = cls.figs.pop(num)
+            except KeyError:
+                return
         manager.canvas.mpl_disconnect(manager._cidgcf)
         manager.destroy()
         gc.collect(1)
@@ -62,8 +71,7 @@ def destroy_fig(cls, fig):
         """Destroy figure *fig*."""
         canvas = getattr(fig, "canvas", None)
         manager = getattr(canvas, "manager", None)
-        num = getattr(manager, "num", None)
-        cls.destroy(num)
+        cls.destroy(manager)
 
     @classmethod
     def destroy_all(cls):

diff --git a/lib/matplotlib/backends/_backend_tk.py b/lib/matplotlib/backends/_backend_tk.py
@@ -456,7 +456,7 @@ def show(self):
             if not self._shown:
                 def destroy(*args):
                     self.window = None
-                    Gcf.destroy(self.num)
+                    Gcf.destroy(self)
                 self.canvas._tkcanvas.bind("<Destroy>", destroy)
                 self.window.deiconify()
             else:

diff --git a/lib/matplotlib/backends/backend_gtk3.py b/lib/matplotlib/backends/backend_gtk3.py
@@ -367,10 +367,8 @@ def add_widget(child):
 
         self.window.set_default_size(w, h)
 
-        def destroy(*args):
-            Gcf.destroy(num)
-        self.window.connect("destroy", destroy)
-        self.window.connect("delete_event", destroy)
+        self.window.connect("destroy", lambda *args: Gcf.destroy(self))
+        self.window.connect("delete_event", lambda *args: Gcf.destroy(self))
         if mpl.is_interactive():
             self.window.show()
             self.canvas.draw_idle()

diff --git a/lib/matplotlib/backends/backend_macosx.py b/lib/matplotlib/backends/backend_macosx.py
@@ -106,7 +106,7 @@ def __init__(self, canvas, num):
             self.canvas.draw_idle()
 
     def close(self):
-        Gcf.destroy(self.num)
+        Gcf.destroy(self)
 
 
 class NavigationToolbar2Mac(_macosx.NavigationToolbar2, NavigationToolbar2):

diff --git a/lib/matplotlib/backends/backend_nbagg.py b/lib/matplotlib/backends/backend_nbagg.py
@@ -231,7 +231,7 @@ def new_figure_manager_given_figure(num, figure):
         if is_interactive():
             manager.show()
             figure.canvas.draw_idle()
-        canvas.mpl_connect('close_event', lambda event: Gcf.destroy(num))
+        canvas.mpl_connect('close_event', lambda event: Gcf.destroy(manager))
         return manager
 
     @staticmethod

diff --git a/lib/matplotlib/backends/backend_qt5.py b/lib/matplotlib/backends/backend_qt5.py
@@ -590,7 +590,7 @@ def _widgetclosed(self):
             return
         self.window._destroying = True
         try:
-            Gcf.destroy(self.num)
+            Gcf.destroy(self)
         except AttributeError:
             pass
             # It seems that when the python session is killed,

diff --git a/lib/matplotlib/backends/backend_wx.py b/lib/matplotlib/backends/backend_wx.py
@@ -1007,7 +1007,7 @@ def _onClose(self, event):
         _log.debug("%s - onClose()", type(self))
         self.canvas.close_event()
         self.canvas.stop_event_loop()
-        Gcf.destroy(self.num)
+        Gcf.destroy(self)
         # self.Destroy()
 
     def GetToolBar(self):

diff --git a/lib/matplotlib/pyplot.py b/lib/matplotlib/pyplot.py
@@ -690,7 +690,7 @@ def close(fig=None):
         if figManager is None:
             return
         else:
-            _pylab_helpers.Gcf.destroy(figManager.num)
+            _pylab_helpers.Gcf.destroy(figManager)
     elif fig == 'all':
         _pylab_helpers.Gcf.destroy_all()
     elif isinstance(fig, int):