remove unregister trait-change callback in ExtensionManager.__del__

minrk · minrk · commit dc1d1d4e8168 · 2015-11-27T00:05:44.000+01:00
Due to reference cycles, this can never be called at a time when it would matter,
but seems to cause weird crashes sometimes during interpreter teardown on Python 3.5 with traitlets 4.1.
diff --git a/IPython/core/extensions.py b/IPython/core/extensions.py
@@ -59,11 +59,6 @@ def __init__(self, shell=None, **kwargs):
         )
         self.loaded = set()
 
-    def __del__(self):
-        self.shell.on_trait_change(
-            self._on_ipython_dir_changed, 'ipython_dir', remove=True
-        )
-
     @property
     def ipython_extension_dir(self):
         return os.path.join(self.shell.ipython_dir, u'extensions')
