Handle None in replace_from_channel (bug 1291)

If there is no active podcast at the moment, the
episode list should be an empty one.

src/gpodder/gtkui/frmntl/model.py

@@ -405,7 +405,11 @@ def replace_from_channel(self, channel, downloading=None, \
         self._all_episodes_view = getattr(channel, 'ALL_EPISODES_PROXY', False)
 
         old_length = len(self._episodes)
-        self._episodes = channel.get_all_episodes()
+        # Avoid gPodder bug 1291
+        if channel is None:
+            self._episodes = []
+        else:
+            self._episodes = channel.get_all_episodes()
         new_length = len(self._episodes)
 
         for i in range(min(old_length, new_length)):

src/gpodder/gtkui/model.py

@@ -196,7 +196,12 @@ def replace_from_channel(self, channel, downloading=None, \
 
         self._all_episodes_view = getattr(channel, 'ALL_EPISODES_PROXY', False)
 
-        episodes = channel.get_all_episodes()
+        # Avoid gPodder bug 1291
+        if channel is None:
+            episodes = []
+        else:
+            episodes = channel.get_all_episodes()
+
         if not isinstance(episodes, list):
             episodes = list(episodes)
         count = len(episodes)