More tests for cancelling streamed run (#590)

tests/fake_model.py

@@ -127,7 +127,10 @@ class FakeModel(Model):
             )
 
 
-def get_response_obj(output: list[TResponseOutputItem], response_id: str | None = None) -> Response:
+def get_response_obj(
+    output: list[TResponseOutputItem],
+    response_id: str | None = None,
+) -> Response:
     return Response(
         id=response_id or "123",
         created_at=123,

tests/test_cancel_streaming.py

@@ -1,12 +1,15 @@
+import json
+
 import pytest
 
 from agents import Agent, Runner
 
 from .fake_model import FakeModel
+from .test_responses import get_function_tool, get_function_tool_call, get_text_message
 
 
 @pytest.mark.asyncio
-async def test_joker_streamed_jokes_with_cancel():
+async def test_simple_streaming_with_cancel():
     model = FakeModel()
     agent = Agent(name="Joker", model=model)
 
@@ -16,7 +19,98 @@ async def test_joker_streamed_jokes_with_cancel():
 
     async for _event in result.stream_events():
         num_events += 1
-        if num_events == 1:
+        if num_events == stop_after:
             result.cancel()
 
     assert num_events == 1, f"Expected {stop_after} visible events, but got {num_events}"
+
+
+@pytest.mark.asyncio
+async def test_multiple_events_streaming_with_cancel():
+    model = FakeModel()
+    agent = Agent(
+        name="Joker",
+        model=model,
+        tools=[get_function_tool("foo", "tool_result")],
+    )
+
+    model.add_multiple_turn_outputs(
+        [
+            # First turn: a message and tool call
+            [
+                get_text_message("a_message"),
+                get_function_tool_call("foo", json.dumps({"a": "b"})),
+            ],
+            # Second turn: text message
+            [get_text_message("done")],
+        ]
+    )
+
+    result = Runner.run_streamed(agent, input="Please tell me 5 jokes.")
+    num_events = 0
+    stop_after = 2
+
+    async for _ in result.stream_events():
+        num_events += 1
+        if num_events == stop_after:
+            result.cancel()
+
+    assert num_events == stop_after, f"Expected {stop_after} visible events, but got {num_events}"
+
+
+@pytest.mark.asyncio
+async def test_cancel_prevents_further_events():
+    model = FakeModel()
+    agent = Agent(name="Joker", model=model)
+    result = Runner.run_streamed(agent, input="Please tell me 5 jokes.")
+    events = []
+    async for event in result.stream_events():
+        events.append(event)
+        result.cancel()
+        break  # Cancel after first event
+    # Try to get more events after cancel
+    more_events = [e async for e in result.stream_events()]
+    assert len(events) == 1
+    assert more_events == [], "No events should be yielded after cancel()"
+
+
+@pytest.mark.asyncio
+async def test_cancel_is_idempotent():
+    model = FakeModel()
+    agent = Agent(name="Joker", model=model)
+    result = Runner.run_streamed(agent, input="Please tell me 5 jokes.")
+    events = []
+    async for event in result.stream_events():
+        events.append(event)
+        result.cancel()
+        result.cancel()  # Call cancel again
+        break
+    # Should not raise or misbehave
+    assert len(events) == 1
+
+
+@pytest.mark.asyncio
+async def test_cancel_before_streaming():
+    model = FakeModel()
+    agent = Agent(name="Joker", model=model)
+    result = Runner.run_streamed(agent, input="Please tell me 5 jokes.")
+    result.cancel()  # Cancel before streaming
+    events = [e async for e in result.stream_events()]
+    assert events == [], "No events should be yielded if cancel() is called before streaming."
+
+
+@pytest.mark.asyncio
+async def test_cancel_cleans_up_resources():
+    model = FakeModel()
+    agent = Agent(name="Joker", model=model)
+    result = Runner.run_streamed(agent, input="Please tell me 5 jokes.")
+    # Start streaming, then cancel
+    async for _ in result.stream_events():
+        result.cancel()
+        break
+    # After cancel, queues should be empty and is_complete True
+    assert result.is_complete, "Result should be marked complete after cancel."
+    assert result._event_queue.empty(), "Event queue should be empty after cancel."
+    assert result._input_guardrail_queue.empty(), (
+        "Input guardrail queue should be empty after cancel."
+    )