test(router): monkeypatch _pipeline.run instead of nl2sql.Pipeline.run

app/routers/nl2sql.py

@@ -1,30 +1,31 @@
 from dataclasses import asdict, is_dataclass
+import os
+from pathlib import Path
+import time
+import json
+import uuid
+from typing import Union, Optional, Dict, TypedDict, Any, cast
+
 from fastapi import APIRouter, HTTPException, UploadFile, File
+
 from app.schemas import NL2SQLRequest, NL2SQLResponse, ClarifyResponse
 from nl2sql.pipeline import Pipeline as _Pipeline, FinalResult as _FinalResult
 from nl2sql.ambiguity_detector import AmbiguityDetector
 from nl2sql.safety import Safety
 from nl2sql.planner import Planner
 from nl2sql.generator import Generator
-from adapters.llm.openai_provider import OpenAIProvider
 from nl2sql.executor import Executor
 from nl2sql.verifier import Verifier
 from nl2sql.repair import Repair
+from adapters.llm.openai_provider import OpenAIProvider
 from adapters.db.sqlite_adapter import SQLiteAdapter
 from adapters.db.postgres_adapter import PostgresAdapter
 
-import os
-from pathlib import Path
-import time
-import json
-import uuid
-from typing import Union, Optional, Dict, TypedDict, Any, cast
-
-# Re-export for tests & public API stability (pytest expects nl2sql.Pipeline)
 Pipeline = _Pipeline
 FinalResult = _FinalResult
 __all__ = ["Pipeline", "FinalResult"]
 
+
 router = APIRouter(prefix="/nl2sql")
 
 # -------------------------------

tests/test_nl2sql_router.py

@@ -31,7 +31,7 @@ def test_ambiguity_route(monkeypatch):
             traces=[fake_trace("detector")],
         )
 
-    monkeypatch.setattr(nl2sql.Pipeline, "run", fake_run)
+    monkeypatch.setattr(nl2sql._pipeline, "run", fake_run)
 
     resp = client.post(
         path,
@@ -64,7 +64,7 @@ def test_error_route(monkeypatch):
             traces=[fake_trace("safety")],
         )
 
-    monkeypatch.setattr(nl2sql.Pipeline, "run", fake_run)
+    monkeypatch.setattr(nl2sql._pipeline, "run", fake_run)
 
     resp = client.post(
         path,
@@ -94,7 +94,7 @@ def test_success_route(monkeypatch):
             traces=[fake_trace("planner"), fake_trace("generator")],
         )
 
-    monkeypatch.setattr(nl2sql.Pipeline, "run", fake_run)
+    monkeypatch.setattr(nl2sql._pipeline, "run", fake_run)
 
     resp = client.post(
         path,