migration: establish exact preserved app baseline

app/tests/test_mentor_stream.py

@@ -0,0 +1,108 @@
+from __future__ import annotations
+
+import json
+import unittest
+from pathlib import Path
+from unittest.mock import patch
+
+from mentor_agent import MentorSkill, chat_with_mentor, stream_with_mentor
+
+
+class FakeStreamResponse:
+    def __init__(self, lines: list[bytes]) -> None:
+        self.lines = lines
+
+    def __enter__(self):
+        return iter(self.lines)
+
+    def __exit__(self, exc_type, exc_value, traceback):
+        return False
+
+
+class MentorStreamTests(unittest.TestCase):
+    def setUp(self) -> None:
+        self.skill = MentorSkill(
+            skill_id="test-mentor",
+            name="测试老师",
+            description="测试",
+            tagline="先看事实",
+            focus=("纪律",),
+            content="只做条件化判断。",
+            path=Path("SKILL.md"),
+        )
+        self.lines = [
+            b'data: {"choices":[{"delta":{"content":"first"}}]}\n',
+            b'data: {"choices":[{"delta":{"content":" second"}}]}\n',
+            b"data: [DONE]\n",
+        ]
+
+    def test_stream_requests_upstream_streaming_and_yields_deltas(self):
+        captured = {}
+
+        def open_request(request, timeout):
+            captured["payload"] = json.loads(request.data.decode("utf-8"))
+            captured["accept"] = request.headers.get("Accept")
+            return FakeStreamResponse(self.lines)
+
+        with patch("mentor_agent.urllib.request.urlopen", side_effect=open_request):
+            chunks = list(
+                stream_with_mentor(
+                    self.skill, {"data_trade_date": "20260723"}, "怎么看？", [],
+                    "key", "https://example.test/v1", "model",
+                )
+            )
+
+        self.assertEqual(chunks, ["first", " second"])
+        self.assertTrue(captured["payload"]["stream"])
+        self.assertEqual(captured["accept"], "text/event-stream")
+
+    def test_non_streaming_compatibility_wrapper_collects_chunks(self):
+        with patch(
+            "mentor_agent.urllib.request.urlopen",
+            return_value=FakeStreamResponse(self.lines),
+        ):
+            result = chat_with_mentor(
+                self.skill, {}, "怎么看？", [], "key", "https://example.test/v1", "model"
+            )
+        self.assertEqual(result["answer"], "first second")
+
+    def test_final_full_message_does_not_duplicate_streamed_deltas(self):
+        lines = [
+            b'data: {"choices":[{"delta":{"content":"first"}}]}\n',
+            b'data: {"choices":[{"delta":{"content":" second"}}]}\n',
+            b'data: {"choices":[{"message":{"content":"first second"}}]}\n',
+            b"data: [DONE]\n",
+        ]
+        with patch(
+            "mentor_agent.urllib.request.urlopen",
+            return_value=FakeStreamResponse(lines),
+        ):
+            chunks = list(
+                stream_with_mentor(
+                    self.skill, {}, "question", [], "key",
+                    "https://example.test/v1", "model",
+                )
+            )
+        self.assertEqual(chunks, ["first", " second"])
+
+    def test_snapshot_only_stream_emits_only_new_suffix(self):
+        lines = [
+            b'data: {"choices":[{"message":{"content":"first"}}]}\n',
+            b'data: {"choices":[{"message":{"content":"first second"}}]}\n',
+            b"data: [DONE]\n",
+        ]
+        with patch(
+            "mentor_agent.urllib.request.urlopen",
+            return_value=FakeStreamResponse(lines),
+        ):
+            chunks = list(
+                stream_with_mentor(
+                    self.skill, {}, "question", [], "key",
+                    "https://example.test/v1", "model",
+                )
+            )
+        self.assertEqual(chunks, ["first", " second"])
+
+
+if __name__ == "__main__":
+    unittest.main()