V4.2 complete

tests/test_v42_evidence.py

@@ -33,6 +33,18 @@ from transcription.services.sources import TranscriptionError
 from transcription.services.sources import transcribe_document_image
 
 
+class _ChunkedAsyncStream(httpx.AsyncByteStream):
+    def __init__(self, chunks: list[bytes]):
+        self._chunks = chunks
+
+    async def __aiter__(self):
+        for chunk in self._chunks:
+            yield chunk
+
+    async def aclose(self):
+        return
+
+
 @pytest.mark.asyncio
 async def test_openrouter_captures_exact_transport_and_secret_safe_manifest():
     response_body = (
@@ -87,6 +99,39 @@ async def test_openrouter_captures_exact_transport_and_secret_safe_manifest():
     assert result.request_manifest.omitted_optional_parameters == ("temperature", "top_p")
 
 
+@pytest.mark.asyncio
+async def test_openrouter_captures_body_consumed_as_sdk_stream():
+    response_body = (
+        b'{"id":"gen-2","created":1,"model":"vendor/model","object":"chat.completion",'
+        b'"system_fingerprint":null,"choices":[{"index":0,"finish_reason":"stop",'
+        b'"message":{"role":"assistant","content":"Transcript"}}],'
+        b'"unknown_streamed_field":true}'
+    )
+
+    async def handler(request: httpx.Request) -> httpx.Response:
+        return httpx.Response(
+            200,
+            stream=_ChunkedAsyncStream([response_body[:23], response_body[23:61], response_body[61:]]),
+            headers={"Content-Type": "application/json"},
+            request=request,
+        )
+
+    provider = OpenRouterTranscriptionProvider(
+        settings=Settings(openrouter_api_key="test-key"),
+        async_client=httpx.AsyncClient(transport=httpx.MockTransport(handler)),
+    )
+    result = await provider.transcribe(
+        prompt_text="Literal prompt",
+        image_bytes=b"source-bytes",
+        mime_type="image/png",
+    )
+
+    assert result.transport_evidence is not None
+    assert result.transport_evidence.body == response_body
+    assert b'"unknown_streamed_field":true' in result.transport_evidence.body
+    await provider.aclose()
+
+
 @pytest.mark.asyncio
 async def test_openrouter_failure_retains_safe_response_evidence():
     async def handler(request: httpx.Request) -> httpx.Response:
@@ -113,6 +158,7 @@ async def test_openrouter_failure_retains_safe_response_evidence():
     assert evidence.status_code == 500
     assert evidence.body == b'{"error":{"message":"provider unavailable"}}'
     assert evidence.safe_headers == {"content-type": "application/json", "retry-after": "2"}
+    assert str(failure.value) == "OpenRouter request failed with HTTP 500: provider unavailable"
 
 
 @pytest.mark.asyncio