test: improve deterministic unit test coverage

tests/agent/test_runner_injections.py

@@ -4,7 +4,6 @@ from __future__ import annotations
 
 import asyncio
 import base64
-import time
 from unittest.mock import AsyncMock, MagicMock, patch
 
 import pytest
@@ -35,15 +34,15 @@ def _make_loop(tmp_path):
 
     with patch("nanobot.agent.loop.ContextBuilder"), \
          patch("nanobot.agent.loop.SessionManager"), \
-         patch("nanobot.agent.loop.SubagentManager") as MockSubMgr:
-        MockSubMgr.return_value.cancel_by_session = AsyncMock(return_value=0)
+         patch("nanobot.agent.loop.SubagentManager") as mock_sub_mgr:
+        mock_sub_mgr.return_value.cancel_by_session = AsyncMock(return_value=0)
         loop = AgentLoop(bus=bus, provider=provider, workspace=tmp_path)
     return loop
 
 @pytest.mark.asyncio
 async def test_drain_injections_returns_empty_when_no_callback():
     """No injection_callback → empty list."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
 
     provider = MagicMock()
     runner = AgentRunner(provider)
@@ -61,7 +60,7 @@ async def test_drain_injections_returns_empty_when_no_callback():
 @pytest.mark.asyncio
 async def test_drain_injections_extracts_content_from_inbound_messages():
     """Should extract .content from InboundMessage objects."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -92,7 +91,7 @@ async def test_drain_injections_extracts_content_from_inbound_messages():
 @pytest.mark.asyncio
 async def test_drain_injections_passes_limit_to_callback_when_supported():
     """Limit-aware callbacks can preserve overflow in their own queue."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner, _MAX_INJECTIONS_PER_TURN
+    from nanobot.agent.runner import _MAX_INJECTIONS_PER_TURN, AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -127,7 +126,7 @@ async def test_drain_injections_passes_limit_to_callback_when_supported():
 @pytest.mark.asyncio
 async def test_drain_injections_skips_empty_content():
     """Messages with blank content should be filtered out."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -156,7 +155,7 @@ async def test_drain_injections_skips_empty_content():
 @pytest.mark.asyncio
 async def test_drain_injections_handles_callback_exception():
     """If the callback raises, return empty list (error is logged)."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
 
     provider = MagicMock()
     runner = AgentRunner(provider)
@@ -178,7 +177,7 @@ async def test_drain_injections_handles_callback_exception():
 @pytest.mark.asyncio
 async def test_checkpoint1_injects_after_tool_execution():
     """Follow-up messages are injected after tool execution, before next LLM call."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -231,8 +230,8 @@ async def test_checkpoint1_injects_after_tool_execution():
 @pytest.mark.asyncio
 async def test_checkpoint2_injects_after_final_response_with_resuming_stream():
     """After final response, if injections exist, stream_end should get resuming=True."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
     from nanobot.agent.hook import AgentHook, AgentHookContext
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -290,7 +289,7 @@ async def test_checkpoint2_injects_after_final_response_with_resuming_stream():
 @pytest.mark.asyncio
 async def test_checkpoint2_preserves_final_response_in_history_before_followup():
     """A follow-up injected after a final answer must still see that answer in history."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -405,7 +404,7 @@ async def test_loop_injected_followup_preserves_image_media(tmp_path):
 @pytest.mark.asyncio
 async def test_runner_merges_multiple_injected_user_messages_without_losing_media():
     """Multiple injected follow-ups should not create lossy consecutive user messages."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
 
     provider = MagicMock()
     call_count = {"n": 0}
@@ -468,7 +467,7 @@ async def test_runner_merges_multiple_injected_user_messages_without_losing_medi
 @pytest.mark.asyncio
 async def test_injection_cycles_capped_at_max():
     """Injection cycles should be capped at _MAX_INJECTION_CYCLES."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner, _MAX_INJECTION_CYCLES
+    from nanobot.agent.runner import _MAX_INJECTION_CYCLES, AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -509,7 +508,7 @@ async def test_injection_cycles_capped_at_max():
 @pytest.mark.asyncio
 async def test_no_injections_flag_is_false_by_default():
     """had_injections should be False when no injection callback or no messages."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
 
     provider = MagicMock()
 
@@ -607,16 +606,12 @@ async def test_followup_routed_to_pending_queue(tmp_path):
     msg = InboundMessage(channel="discord", sender_id="u", chat_id="c", content="follow-up")
     await loop.bus.publish_inbound(msg)
 
-    deadline = time.time() + 2
-    while pending.empty() and time.time() < deadline:
-        await asyncio.sleep(0.01)
+    queued_msg = await asyncio.wait_for(pending.get(), timeout=2)
 
     loop.stop()
     await asyncio.wait_for(run_task, timeout=2)
 
     assert loop._dispatch.await_count == 0
-    assert not pending.empty()
-    queued_msg = pending.get_nowait()
     assert queued_msg.content == "follow-up"
     assert queued_msg.session_key == UNIFIED_SESSION_KEY
 
@@ -625,9 +620,9 @@ async def test_followup_routed_to_pending_queue(tmp_path):
 async def test_pending_queue_preserves_overflow_for_next_injection_cycle(tmp_path):
     """Pending queue should leave overflow messages queued for later drains."""
     from nanobot.agent.loop import AgentLoop
+    from nanobot.agent.runner import _MAX_INJECTIONS_PER_TURN
     from nanobot.bus.events import InboundMessage
     from nanobot.bus.queue import MessageBus
-    from nanobot.agent.runner import _MAX_INJECTIONS_PER_TURN
 
     bus = MessageBus()
     provider = MagicMock()
@@ -680,7 +675,12 @@ async def test_pending_queue_full_falls_back_to_queued_task(tmp_path):
     from nanobot.bus.events import InboundMessage
 
     loop = _make_loop(tmp_path)
-    loop._dispatch = AsyncMock()  # type: ignore[method-assign]
+    dispatched = asyncio.Event()
+
+    async def _dispatch(_msg):
+        dispatched.set()
+
+    loop._dispatch = AsyncMock(side_effect=_dispatch)  # type: ignore[method-assign]
 
     pending = asyncio.Queue(maxsize=1)
     pending.put_nowait(InboundMessage(channel="cli", sender_id="u", chat_id="c", content="already queued"))
@@ -690,9 +690,7 @@ async def test_pending_queue_full_falls_back_to_queued_task(tmp_path):
     msg = InboundMessage(channel="cli", sender_id="u", chat_id="c", content="follow-up")
     await loop.bus.publish_inbound(msg)
 
-    deadline = time.time() + 2
-    while loop._dispatch.await_count == 0 and time.time() < deadline:
-        await asyncio.sleep(0.01)
+    await asyncio.wait_for(dispatched.wait(), timeout=2)
 
     loop.stop()
     await asyncio.wait_for(run_task, timeout=2)
@@ -750,7 +748,7 @@ async def test_dispatch_republishes_leftover_queue_messages(tmp_path):
 @pytest.mark.asyncio
 async def test_drain_injections_on_fatal_tool_error():
     """Pending injections should be drained even when a fatal tool error occurs."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -803,7 +801,7 @@ async def test_drain_injections_on_fatal_tool_error():
 @pytest.mark.asyncio
 async def test_drain_injections_on_llm_error():
     """Pending injections should be drained when the LLM returns an error finish_reason."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -858,7 +856,7 @@ async def test_drain_injections_on_llm_error():
 @pytest.mark.asyncio
 async def test_drain_injections_on_empty_final_response():
     """Pending injections should be drained when the runner exits due to empty response."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner, _MAX_EMPTY_RETRIES
+    from nanobot.agent.runner import _MAX_EMPTY_RETRIES, AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -913,7 +911,7 @@ async def test_drain_injections_on_max_iterations():
     injections are appended to messages but not processed by the LLM.
     The key point is they are consumed from the queue to prevent re-publish.
     """
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -965,7 +963,7 @@ async def test_drain_injections_on_max_iterations():
 async def test_drain_injections_set_flag_when_followup_arrives_after_last_iteration():
     """Late follow-ups drained in max_iterations should still flip had_injections."""
     from nanobot.agent.hook import AgentHook
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner
+    from nanobot.agent.runner import AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()
@@ -1027,7 +1025,7 @@ async def test_drain_injections_set_flag_when_followup_arrives_after_last_iterat
 @pytest.mark.asyncio
 async def test_injection_cycle_cap_on_error_path():
     """Injection cycles should be capped even when every iteration hits an LLM error."""
-    from nanobot.agent.runner import AgentRunSpec, AgentRunner, _MAX_INJECTION_CYCLES
+    from nanobot.agent.runner import _MAX_INJECTION_CYCLES, AgentRunner, AgentRunSpec
     from nanobot.bus.events import InboundMessage
 
     provider = MagicMock()