Better way to leave the dummy room

src/irc/irc_client.hpp

@@ -198,6 +198,11 @@ public:
    * Get a reference to the unique dummy channel
    */
   DummyIrcChannel& get_dummy_channel();
+  /**
+   * Leave the dummy channel: forward a message to the user to indicate that
+   * he left it, and mark it as not joined.
+   */
+  void leave_dummy_channel(const std::string& exit_message);
 
   const std::string& get_hostname() const { return this->hostname; }
   std::string get_nick() const { return this->current_nick; }