test: add SQLite session fixture for providers (#38982)

api/providers/conftest.py

@@ -0,0 +1,35 @@
+"""Shared database fixtures for provider tests.
+
+Provider tests live outside ``tests/unit_tests`` and therefore cannot use that
+suite's SQLite fixtures. Keep this fixture scoped to ``providers`` so each
+provider package can exercise real SQLAlchemy queries without a service
+database or mocked sessions.
+"""
+
+from collections.abc import Iterator
+
+import pytest
+from sqlalchemy import create_engine
+from sqlalchemy.orm import Session
+
+from models.base import TypeBase
+
+
+@pytest.fixture
+def sqlite3_session(request: pytest.FixtureRequest) -> Iterator[Session]:
+    """Yield an isolated SQLite session with the parametrized model tables.
+
+    Pass the required ORM classes through indirect parametrization. The engine
+    is per-test so committed rows and identity-map state cannot leak between
+    provider packages.
+    """
+
+    models: tuple[type[TypeBase], ...] = request.param
+    engine = create_engine("sqlite:///:memory:")
+    tables = [model.metadata.tables[model.__tablename__] for model in models]
+    TypeBase.metadata.create_all(engine, tables=tables)
+    try:
+        with Session(engine, expire_on_commit=False) as session:
+            yield session
+    finally:
+        engine.dispose()