From be5f5054101a7731477b632b13fc4f105f890a32 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=EB=B0=95=EC=83=81=ED=98=B8=20Sangho=20Park?=
 <ps040211@gmail.com>
Date: Wed, 12 Aug 2026 17:39:15 +0900
Subject: [PATCH] fix: normalize faster-whisper TranscriptionInfo to dict
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Colab run 4 (A100): same namedtuple bug as segments — faster-whisper
returns TranscriptionInfo (namedtuple) but batch.py reads
outcome['info'].get('language') -> AttributeError 'TranscriptionInfo'
object has no attribute 'get' on every real transcription, failing the
CLI, API auto-worker job, worker drain, and bench clip alike.

FasterWhisperEngine now normalizes info to a dict at the boundary
(_to_dict_info: _asdict -> dataclasses.asdict -> known-field fallback).

+ 2 unit tests (namedtuple/dict info); 138 tests pass, ruff clean.
---
 .../engine/faster_whisper_engine.py           | 28 ++++++++++++++-
 tests/unit/test_engine_faster_whisper.py      | 36 +++++++++++++++++--
 2 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/src/luke_scribe/engine/faster_whisper_engine.py b/src/luke_scribe/engine/faster_whisper_engine.py
index 31a8be0..0d2a914 100644
--- a/src/luke_scribe/engine/faster_whisper_engine.py
+++ b/src/luke_scribe/engine/faster_whisper_engine.py
@@ -133,7 +133,7 @@ class FasterWhisperEngine(TranscriptionEngine):
         wrapped = _CancellableSegmentIterator(
             self._to_dict_segments(segments_iter), should_cancel or (lambda: False)
         )
-        return TranscriptionOutcome(wrapped, info=info)
+        return TranscriptionOutcome(wrapped, info=self._to_dict_info(info))
 
     @staticmethod
     def _to_dict_segments(segments):
@@ -169,6 +169,32 @@ class FasterWhisperEngine(TranscriptionEngine):
                 if (v := getattr(seg, k, None)) is not None
             }
 
+    @staticmethod
+    def _to_dict_info(info):
+        """faster-whisper TranscriptionInfo(namedtuple) → dict.
+
+        다운스트림(배치 파이프라인)은 info를 dict 계약으로 접근한다
+        (``info.get("language")``) — GPU 실전에서만 재현되는 버그:
+        'TranscriptionInfo' object has no attribute 'get'.
+        """
+        if info is None or isinstance(info, dict):
+            return info
+        asdict = getattr(info, "_asdict", None)
+        if asdict is not None:
+            return dict(asdict())
+        try:
+            import dataclasses
+
+            if dataclasses.is_dataclass(info):
+                return dataclasses.asdict(info)
+        except Exception:
+            pass
+        return {
+            k: v
+            for k in ("language", "language_probability", "duration", "duration_after_vad")
+            if (v := getattr(info, k, None)) is not None
+        }
+
     @staticmethod
     def _split_device(device: str) -> tuple[str, int]:
         """'cuda:N' → ('cuda', N). CTranslate2는 device='cuda'만 허용하므로 분리한다.
diff --git a/tests/unit/test_engine_faster_whisper.py b/tests/unit/test_engine_faster_whisper.py
index 081ca38..5ca618f 100644
--- a/tests/unit/test_engine_faster_whisper.py
+++ b/tests/unit/test_engine_faster_whisper.py
@@ -16,17 +16,18 @@ from luke_scribe.engine.faster_whisper_engine import FasterWhisperEngine
 
 
 class FakeWhisperModel:
-    """faster_whisper.WhisperModel 대체 — 생성 인자/세그먼트를 기록한다."""
+    """faster_whisper.WhisperModel 대체 — 생성 인자/세그먼트/info를 기록한다."""
 
     calls: list[dict] = []
     segments: list = []  # transcribe()가 yield할 세그먼트 (기본: namedtuple)
+    info: object = None  # 기본: TranscriptionInfo(namedtuple) 흉내
 
     def __init__(self, *args, **kwargs) -> None:
         self.kwargs = kwargs
         self.__class__.calls.append(kwargs)
 
     def transcribe(self, audio_path, **kwargs):
-        return iter(list(self.__class__.segments)), {}
+        return iter(list(self.__class__.segments)), self.__class__.info
 
 
 def _install_fake(monkeypatch) -> None:
@@ -35,6 +36,7 @@ def _install_fake(monkeypatch) -> None:
     monkeypatch.setitem(sys.modules, "faster_whisper", mod)
     FakeWhisperModel.calls.clear()
     FakeWhisperModel.segments = []
+    FakeWhisperModel.info = None
 
 
 def _opts(**kw) -> TranscriptionOptions:
@@ -137,3 +139,33 @@ def test_dict_segments_passthrough(monkeypatch):
     )
     segs = list(outcome.segments)
     assert segs == [{"index": 0, "start": 0.0, "end": 1.0, "text": "x"}]
+
+
+def test_namedtuple_info_normalized_to_dict(monkeypatch):
+    """faster-whisper TranscriptionInfo(namedtuple) → dict (GPU 실전 버그)."""
+    from collections import namedtuple
+
+    _install_fake(monkeypatch)
+    Info = namedtuple(
+        "TranscriptionInfo",
+        ["language", "language_probability", "duration", "duration_after_vad"],
+    )
+    FakeWhisperModel.info = Info(
+        language="ko", language_probability=0.99, duration=10.464, duration_after_vad=9.088
+    )
+    outcome = FasterWhisperEngine().transcribe(
+        "/tmp/x.wav", _opts(device="cpu", compute_type="int8")
+    )
+    # dict 계약: .get() 사용 가능 (batch.py가 이걸로 접근)
+    assert outcome.info.get("language") == "ko"
+    assert outcome.info.get("duration") == 10.464
+
+
+def test_dict_info_passthrough(monkeypatch):
+    """이미 dict인 info는 그대로 (mock 계약과 호환)."""
+    _install_fake(monkeypatch)
+    FakeWhisperModel.info = {"language": "ko"}
+    outcome = FasterWhisperEngine().transcribe(
+        "/tmp/x.wav", _opts(device="cpu", compute_type="int8")
+    )
+    assert outcome.info == {"language": "ko"}