test(responses): fold the bridged streaming regressions into the mapped test file

tests/test_litellm/responses/litellm_completion_transformation/test_streaming_iterator.py

@@ -1,130 +0,0 @@
-from unittest.mock import MagicMock
-
-import pytest
-
-from litellm.responses.litellm_completion_transformation.streaming_iterator import (
-    LiteLLMCompletionStreamingIterator,
-)
-from litellm.responses.utils import ResponsesAPIRequestUtils
-from litellm.types.utils import Delta, ModelResponseStream, StreamingChoices
-
-CHAT_COMPLETION_ID = "chatcmpl-77d33d09-effa-4cd2-9c0d-c742d4358256"
-RESPONSE_ID_EVENT_TYPES = frozenset(
-    {"response.created", "response.in_progress", "response.completed"}
-)
-
-
-def _chunk(content: str, finish_reason: str | None = None) -> ModelResponseStream:
-    return ModelResponseStream(
-        id=CHAT_COMPLETION_ID,
-        created=1748575031,
-        model="claude-haiku-4-5",
-        object="chat.completion.chunk",
-        choices=[
-            StreamingChoices(
-                index=0,
-                delta=Delta(role="assistant", content=content),
-                finish_reason=finish_reason,
-            )
-        ],
-    )
-
-
-class _FakeStreamWrapper:
-    def __init__(self, chunks):
-        self._chunks = list(chunks)
-        self.logging_obj = MagicMock()
-
-    def __iter__(self):
-        return self
-
-    def __next__(self):
-        if not self._chunks:
-            raise StopIteration
-        return self._chunks.pop(0)
-
-    def __aiter__(self):
-        return self
-
-    async def __anext__(self):
-        if not self._chunks:
-            raise StopAsyncIteration
-        return self._chunks.pop(0)
-
-
-def _build_iterator(chunks) -> LiteLLMCompletionStreamingIterator:
-    return LiteLLMCompletionStreamingIterator(
-        model="claude-haiku-4-5",
-        litellm_custom_stream_wrapper=_FakeStreamWrapper(chunks),
-        request_input="What is the weather in San Francisco?",
-        responses_api_request={},
-        custom_llm_provider="anthropic",
-        litellm_metadata={},
-    )
-
-
-def _response_ids(events) -> list[str]:
-    return [
-        event.response.id
-        for event in events
-        if getattr(event, "type", None) in RESPONSE_ID_EVENT_TYPES
-    ]
-
-
-@pytest.mark.asyncio
-async def test_streaming_events_share_the_chat_completion_response_id():
-    """
-    Every event of a bridged stream has to carry the same id, and that id has to decode
-    to the chat completion id spend tracking stores as `request_id`. Otherwise a
-    follow-up `previous_response_id` matches no session and the conversation is dropped.
-    """
-    iterator = _build_iterator([_chunk("Hello"), _chunk("!", finish_reason="stop")])
-
-    events = [event async for event in iterator]
-
-    response_ids = _response_ids(events)
-    assert len(response_ids) == 3
-    assert len(set(response_ids)) == 1
-    decoded = ResponsesAPIRequestUtils._decode_responses_api_response_id(response_ids[0])
-    assert decoded["response_id"] == CHAT_COMPLETION_ID
-    assert decoded["custom_llm_provider"] == "anthropic"
-
-
-def test_sync_streaming_events_share_the_chat_completion_response_id():
-    iterator = _build_iterator([_chunk("Hello"), _chunk("!", finish_reason="stop")])
-
-    events = list(iterator)
-
-    response_ids = _response_ids(events)
-    assert len(response_ids) == 3
-    assert len(set(response_ids)) == 1
-    assert (
-        ResponsesAPIRequestUtils._decode_responses_api_response_id(response_ids[0])["response_id"]
-        == CHAT_COMPLETION_ID
-    )
-
-
-@pytest.mark.asyncio
-async def test_streaming_emits_every_chunk_after_priming_the_response_id():
-    iterator = _build_iterator(
-        [_chunk("Hel"), _chunk("lo"), _chunk("!", finish_reason="stop")]
-    )
-
-    events = [event async for event in iterator]
-
-    deltas = "".join(
-        event.delta for event in events if getattr(event, "type", None) == "response.output_text.delta"
-    )
-    assert deltas == "Hello!"
-
-
-@pytest.mark.asyncio
-async def test_streaming_response_id_falls_back_when_upstream_yields_nothing():
-    iterator = _build_iterator([])
-
-    events = [event async for event in iterator]
-
-    response_ids = _response_ids(events)
-    assert response_ids
-    assert len(set(response_ids)) == 1
-    assert response_ids[0].startswith("resp_")

tests/test_litellm/responses/litellm_completion_transformation/test_streaming_iterator_transformation.py

@@ -1,18 +1,23 @@
 """
-Tests for streaming tool-calls in Responses API transformation.
+Tests for the Responses API streaming bridge in
+litellm/responses/litellm_completion_transformation/streaming_iterator.py.
 
 Ensures that when the underlying chat-completions stream includes tool_calls deltas,
 LiteLLM emits Responses API streaming events (output_item.added + function_call_arguments.*).
 
 Also ensures that tool calls that only appear in the final built response still get emitted
-before response.completed.
+before response.completed, and that every event of a bridged stream carries the response id
+spend tracking stores, so a follow-up previous_response_id still finds the conversation.
 """
 
-from unittest.mock import AsyncMock
+from unittest.mock import AsyncMock, MagicMock
+
+import pytest
 
 from litellm.responses.litellm_completion_transformation.streaming_iterator import (
     LiteLLMCompletionStreamingIterator,
 )
+from litellm.responses.utils import ResponsesAPIRequestUtils
 from litellm.types.llms.openai import ResponsesAPIStreamEvents
 from litellm.types.utils import (
     Delta,
@@ -21,6 +26,68 @@ from litellm.types.utils import (
     StreamingChoices,
 )
 
+CHAT_COMPLETION_ID = "chatcmpl-77d33d09-effa-4cd2-9c0d-c742d4358256"
+RESPONSE_ID_EVENT_TYPES = frozenset(
+    {"response.created", "response.in_progress", "response.completed"}
+)
+
+
+def _chunk(content: str, finish_reason: str | None = None) -> ModelResponseStream:
+    return ModelResponseStream(
+        id=CHAT_COMPLETION_ID,
+        created=1748575031,
+        model="claude-haiku-4-5",
+        object="chat.completion.chunk",
+        choices=[
+            StreamingChoices(
+                index=0,
+                delta=Delta(role="assistant", content=content),
+                finish_reason=finish_reason,
+            )
+        ],
+    )
+
+
+class _FakeStreamWrapper:
+    def __init__(self, chunks):
+        self._chunks = list(chunks)
+        self.logging_obj = MagicMock()
+
+    def __iter__(self):
+        return self
+
+    def __next__(self):
+        if not self._chunks:
+            raise StopIteration
+        return self._chunks.pop(0)
+
+    def __aiter__(self):
+        return self
+
+    async def __anext__(self):
+        if not self._chunks:
+            raise StopAsyncIteration
+        return self._chunks.pop(0)
+
+
+def _build_iterator(chunks) -> LiteLLMCompletionStreamingIterator:
+    return LiteLLMCompletionStreamingIterator(
+        model="claude-haiku-4-5",
+        litellm_custom_stream_wrapper=_FakeStreamWrapper(chunks),
+        request_input="What is the weather in San Francisco?",
+        responses_api_request={},
+        custom_llm_provider="anthropic",
+        litellm_metadata={},
+    )
+
+
+def _response_ids(events) -> list[str]:
+    return [
+        event.response.id
+        for event in events
+        if getattr(event, "type", None) in RESPONSE_ID_EVENT_TYPES
+    ]
+
 
 def test_tool_call_delta_is_emitted_as_responses_events():
     iterator = LiteLLMCompletionStreamingIterator(
@@ -397,3 +464,62 @@ def test_reused_index_with_new_call_id_marks_fallback_ambiguous():
     assert arguments_by_call_id["call_b"] == '{"b":'
     assert arguments_by_call_id["call_a"] != '{"a":1}'
     assert arguments_by_call_id["call_b"] != '{"b":1}'
+
+
+@pytest.mark.asyncio
+async def test_streaming_events_share_the_chat_completion_response_id():
+    """
+    Every event of a bridged stream has to carry the same id, and that id has to decode
+    to the chat completion id spend tracking stores as `request_id`. Otherwise a
+    follow-up `previous_response_id` matches no session and the conversation is dropped.
+    """
+    iterator = _build_iterator([_chunk("Hello"), _chunk("!", finish_reason="stop")])
+
+    events = [event async for event in iterator]
+
+    response_ids = _response_ids(events)
+    assert len(response_ids) == 3
+    assert len(set(response_ids)) == 1
+    decoded = ResponsesAPIRequestUtils._decode_responses_api_response_id(response_ids[0])
+    assert decoded["response_id"] == CHAT_COMPLETION_ID
+    assert decoded["custom_llm_provider"] == "anthropic"
+
+
+def test_sync_streaming_events_share_the_chat_completion_response_id():
+    iterator = _build_iterator([_chunk("Hello"), _chunk("!", finish_reason="stop")])
+
+    events = list(iterator)
+
+    response_ids = _response_ids(events)
+    assert len(response_ids) == 3
+    assert len(set(response_ids)) == 1
+    assert (
+        ResponsesAPIRequestUtils._decode_responses_api_response_id(response_ids[0])["response_id"]
+        == CHAT_COMPLETION_ID
+    )
+
+
+@pytest.mark.asyncio
+async def test_streaming_emits_every_chunk_after_priming_the_response_id():
+    iterator = _build_iterator(
+        [_chunk("Hel"), _chunk("lo"), _chunk("!", finish_reason="stop")]
+    )
+
+    events = [event async for event in iterator]
+
+    deltas = "".join(
+        event.delta for event in events if getattr(event, "type", None) == "response.output_text.delta"
+    )
+    assert deltas == "Hello!"
+
+
+@pytest.mark.asyncio
+async def test_streaming_response_id_falls_back_when_upstream_yields_nothing():
+    iterator = _build_iterator([])
+
+    events = [event async for event in iterator]
+
+    response_ids = _response_ids(events)
+    assert response_ids
+    assert len(set(response_ids)) == 1
+    assert response_ids[0].startswith("resp_")