[真实链路自测]：完成完整流程自测和ACK缓冲修正，包含真实Provider验收、播放回声清理和回归测试

tests/test_live_runtime.py

@@ -134,6 +134,7 @@ def make_runtime(
     context: ConversationContext | None = None,
     partial_texts: list[list[str]] | None = None,
     audio_preprocessor: MarkerAudioPreprocessor | None = None,
+    wake_ack_text: str = "我在",
 ) -> tuple[VoiceAssistantPipeline, QueueSttProvider, MockLlmProvider, MemoryAudioTransport, RecordingReporter]:
     frames = []
     for idx, _text in enumerate(texts):
@@ -142,14 +143,14 @@ def make_runtime(
         frames.append(wake_frame(base_id, base_ms))
         partials = partial_texts[idx] if partial_texts and idx < len(partial_texts) else None
         frames.extend(segment_frames(base_id + 1, base_ms + 20, partials=partials))
-    transport = MemoryAudioTransport(frames)
+    transport = MemoryAudioTransport(frames, flush_clears_input=False)
     stt = QueueSttProvider(texts)
     llm = MockLlmProvider(["这是答复。"])
     tts = SineTtsProvider()
     reporter = RecordingReporter()
     event_bus = PipelineEventBus()
     runtime = VoiceAssistantPipeline(
-        config=AppConfig(llm_api_key="secret", speech_provider="cloud"),
+        config=AppConfig(llm_api_key="secret", speech_provider="cloud", wake_ack_text=wake_ack_text),
         transport=transport,
         wakeword=KeywordWakeWordProvider(),
         vad_recorder=VadRecorder(EnergyVadProvider(), min_duration_ms=40, end_silence_ms=40),
@@ -177,6 +178,7 @@ class LiveRuntimeTests(unittest.TestCase):
         self.assertEqual(len(stt.calls), 2)
         self.assertEqual(len(llm.calls), 2)
         self.assertEqual(len(transport.played_segments), 4)
+        self.assertEqual(transport.flush_count, 4)
         self.assertEqual(reporter.transcripts, ["第一问", "第二问"])
         self.assertIn("应答中：我在", reporter.statuses)
         self.assertLess(reporter.statuses.index("唤醒命中"), reporter.statuses.index("应答中：我在"))
@@ -201,6 +203,28 @@ class LiveRuntimeTests(unittest.TestCase):
         positions = [event_types.index(item) for item in expected_order]
         self.assertEqual(positions, sorted(positions))
 
+    def test_zero_post_playback_drain_flushes_without_dropping_prefilled_question(self) -> None:
+        runtime, stt, _, transport, reporter = make_runtime(["第一问"])
+        self.assertEqual(runtime.config.post_playback_drain_ms, 0)
+
+        summary = runtime.run(max_turns=1)
+
+        self.assertEqual(summary.completed_turns, 1)
+        self.assertEqual(reporter.transcripts, ["第一问"])
+        self.assertEqual(len(stt.calls), 1)
+        self.assertEqual(transport.flush_count, 2)
+
+    def test_no_ack_text_does_not_drain_before_capture(self) -> None:
+        runtime, stt, _, transport, reporter = make_runtime(["第一问"], wake_ack_text="")
+
+        summary = runtime.run(max_turns=1)
+
+        self.assertEqual(summary.completed_turns, 1)
+        self.assertEqual(reporter.transcripts, ["第一问"])
+        self.assertEqual(len(stt.calls), 1)
+        self.assertEqual(len(transport.played_segments), 1)
+        self.assertEqual(transport.flush_count, 1)
+
     def test_temporary_context_is_sent_to_second_llm_call(self) -> None:
         runtime, _, llm, _, _ = make_runtime(["第一问", "第二问"])
         runtime.run(max_turns=2)

tests/test_transport.py

@@ -46,8 +46,16 @@ class TransportTests(unittest.TestCase):
         transport = MemoryAudioTransport([frame(1, 0), frame(2, 20)])
         transport.start_input()
         self.assertEqual(transport.flush_input(), 2)
+        self.assertEqual(transport.flush_count, 1)
         self.assertEqual(transport.read_frames(10), [])
 
+    def test_memory_transport_can_preserve_prefilled_frames_on_flush(self) -> None:
+        transport = MemoryAudioTransport([frame(1, 0), frame(2, 20)], flush_clears_input=False)
+        transport.start_input()
+        self.assertEqual(transport.flush_input(), 0)
+        self.assertEqual(transport.flush_count, 1)
+        self.assertEqual([f.frame_id for f in transport.read_frames(10)], [1])
+
     def test_file_replay_roundtrip(self) -> None:
         frames = [frame(1, 0, {"wake": True}), frame(2, 20, {"speech": True})]
         with tempfile.TemporaryDirectory() as tmp: