Enable allow_repeat_speaker to be a list of agents that are allowed to repeat, rather than just a global boolean. (#905)

Co-authored-by: Qingyun Wu <qingyun.wu@psu.edu>

autogen/agentchat/groupchat.py

@@ -30,16 +30,16 @@ class GroupChat:
         - "manual": the next speaker is selected manually by user input.
         - "random": the next speaker is selected randomly.
         - "round_robin": the next speaker is selected in a round robin fashion, i.e., iterating in the same order as provided in `agents`.
-    - allow_repeat_speaker: whether to allow the same speaker to speak consecutively. Default is True.
+    - allow_repeat_speaker: whether to allow the same speaker to speak consecutively. Default is True, in which case all speakers are allowed to speak consecutively. If allow_repeat_speaker is a list of Agents, then only those listed agents are allowed to repeat. If set to False, then no speakers are allowed to repeat.
     """
 
     agents: List[Agent]
     messages: List[Dict]
-    max_round: int = 10
-    admin_name: str = "Admin"
-    func_call_filter: bool = True
-    speaker_selection_method: str = "auto"
-    allow_repeat_speaker: bool = True
+    max_round: Optional[int] = 10
+    admin_name: Optional[str] = "Admin"
+    func_call_filter: Optional[bool] = True
+    speaker_selection_method: Optional[str] = "auto"
+    allow_repeat_speaker: Optional[Union[bool, List[Agent]]] = True
 
     _VALID_SPEAKER_SELECTION_METHODS = ["auto", "manual", "random", "round_robin"]
 
@@ -125,6 +125,13 @@ Then select the next role from {[agent.name for agent in agents]} to play. Only
                 f"It should be one of {self._VALID_SPEAKER_SELECTION_METHODS} (case insensitive). "
             )
 
+        # If provided a list, make sure the agent is in the list
+        allow_repeat_speaker = (
+            self.allow_repeat_speaker
+            if isinstance(self.allow_repeat_speaker, bool)
+            else last_speaker in self.allow_repeat_speaker
+        )
+
         agents = self.agents
         n_agents = len(agents)
         # Warn if GroupChat is underpopulated
@@ -133,7 +140,7 @@ Then select the next role from {[agent.name for agent in agents]} to play. Only
                 f"GroupChat is underpopulated with {n_agents} agents. "
                 "Please add more agents to the GroupChat or use direct communication instead."
             )
-        elif n_agents == 2 and self.speaker_selection_method.lower() != "round_robin" and self.allow_repeat_speaker:
+        elif n_agents == 2 and self.speaker_selection_method.lower() != "round_robin" and allow_repeat_speaker:
             logger.warning(
                 f"GroupChat is underpopulated with {n_agents} agents. "
                 "It is recommended to set speaker_selection_method to 'round_robin' or allow_repeat_speaker to False."
@@ -159,7 +166,7 @@ Then select the next role from {[agent.name for agent in agents]} to play. Only
                         "Please check the function_map of the agents."
                     )
         # remove the last speaker from the list to avoid selecting the same speaker if allow_repeat_speaker is False
-        agents = agents if self.allow_repeat_speaker else [agent for agent in agents if agent != last_speaker]
+        agents = agents if allow_repeat_speaker else [agent for agent in agents if agent != last_speaker]
 
         if self.speaker_selection_method.lower() == "manual":
             selected_agent = self.manual_select_speaker(agents)

test/agentchat/test_groupchat.py

@@ -187,7 +187,7 @@ def _test_n_agents_less_than_3(method):
         messages=[],
         max_round=6,
         speaker_selection_method=method,
-        allow_repeat_speaker=True if method == "random" else False,
+        allow_repeat_speaker=[agent1, agent2] if method == "random" else False,
     )
     group_chat_manager = autogen.GroupChatManager(groupchat=groupchat, llm_config=False)
     agent1.initiate_chat(group_chat_manager, message="This is alice speaking.")
@@ -434,7 +434,7 @@ if __name__ == "__main__":
     # test_broadcast()
     # test_chat_manager()
     # test_plugin()
-    # test_speaker_selection_method()
+    test_speaker_selection_method()
     # test_n_agents_less_than_3()
     # test_agent_mentions()
     # test_termination()