Delete buffer from our own list before closing it

When we close a buffer, weechat invokes a callback so we can unregister
the channel. However, when we close the buffer ourselves in the
unregister function it caused the unregister function to be called
again. By deleting the buffer from our list first, the second invokation
of unregister won't find the channel, so the rest isn't run again.

This prevents an error from weechat when we sent None into buffer_clear
because the channel_buffer had already been set to None.

Also does some cleanup. Use global EVENTROUTER, check if channel exists
instead of catching exception and remove some unnecessary checks.

1 files changed, 13 insertions, 22 deletions

diff --git a/wee_slack.py b/wee_slack.py
index 034d20c..065dc41 100644
--- a/wee_slack.py
+++ b/wee_slack.py
@@ -601,16 +601,12 @@ class WeechatController(object):
         complete
         Adds a weechat buffer to the list of handled buffers for this EventRouter
         """
-        if isinstance(buffer_ptr, basestring):
-            try:
-                self.buffers[buffer_ptr].destroy_buffer(update_remote)
-                if close_buffer:
-                    w.buffer_close(buffer_ptr)
-                del self.buffers[buffer_ptr]
-            except:
-                dbg("Tried to close unknown buffer")
-        else:
-            raise InvalidType(type(buffer_ptr))
+        channel = self.buffers.get(buffer_ptr)
+        if channel:
+            channel.destroy_buffer(update_remote)
+            del self.buffers[buffer_ptr]
+            if close_buffer:
+                w.buffer_close(buffer_ptr)
 
     def get_channel_from_buffer_ptr(self, buffer_ptr):
         return self.buffers.get(buffer_ptr, None)
@@ -684,13 +680,9 @@ def reconnect_callback(*args):
 @utf8_decode
 def buffer_closing_callback(signal, sig_type, data):
     """
-    complete
     Receives a callback from weechat when a buffer is being closed.
-    We pass the eventrouter variable name in as a string, as
-    that is the only way we can do dependency injection via weechat
-    callback, hence the eval.
     """
-    eval(signal).weechat_controller.unregister_buffer(data, True, False)
+    EVENTROUTER.weechat_controller.unregister_buffer(data, True, False)
     return w.WEECHAT_RC_OK
 
 
@@ -1111,6 +1103,9 @@ class SlackTeam(object):
             if w.config_string(w.config_get('irc.look.server_buffer')) == 'merge_with_core':
                 w.buffer_merge(self.channel_buffer, w.buffer_search_main())
 
+    def destroy_buffer(self, update_remote):
+        pass
+
     def set_muted_channels(self, muted_str):
         self.muted_channels = {x for x in muted_str.split(',') if x}
         for channel in self.channels.itervalues():
@@ -1548,9 +1543,7 @@ class SlackChannel(SlackChannelCommon):
 
     def destroy_buffer(self, update_remote):
         self.clear_messages()
-        if self.channel_buffer is not None:
-            self.channel_buffer = None
-        # if update_remote and not eventrouter.shutting_down:
+        self.channel_buffer = None
         self.active = False
         if update_remote and not self.eventrouter.shutting_down:
             s = SlackRequest(self.team.token, SLACK_API_TRANSLATOR[self.type]["leave"], {"channel": self.identifier}, team_hash=self.team.team_hash, channel_identifier=self.identifier)
@@ -2096,10 +2089,8 @@ class SlackThreadChannel(SlackChannelCommon):
         #    w.buffer_set(self.channel_buffer, "hotlist", "1")
 
     def destroy_buffer(self, update_remote):
-        if self.channel_buffer is not None:
-            self.channel_buffer = None
+        self.channel_buffer = None
         self.got_history = False
-        # if update_remote and not eventrouter.shutting_down:
         self.active = False
 
     def render(self, message, force=False):
@@ -3929,7 +3920,7 @@ def setup_hooks():
     w.hook_timer(3000, 0, 0, "reconnect_callback", "EVENTROUTER")
     w.hook_timer(1000 * 60 * 5, 0, 0, "slack_never_away_cb", "")
 
-    w.hook_signal('buffer_closing', "buffer_closing_callback", "EVENTROUTER")
+    w.hook_signal('buffer_closing', "buffer_closing_callback", "")
     w.hook_signal('buffer_switch', "buffer_switch_callback", "EVENTROUTER")
     w.hook_signal('window_switch', "buffer_switch_callback", "EVENTROUTER")
     w.hook_signal('quit', "quit_notification_callback", "")