tests/conftest.py

@@ -87,11 +87,19 @@ def populated_db_b4w(
     Only the first-layer ingestion table is filled; no further processing.
     ``**kwargs`` are forwarded to ``B4wExportFactory.build``; callable values
     are resolved per row (e.g. ``ValDt=lambda: faker.date_between(...)``).
+    ``Id1`` is reserved: it is set per row (``1..row_count``) and cannot be
+    overridden via ``**kwargs``.
+    The returned session is *not* closed by the fixture; close it in the test.
     """
 
     def populate_db_b4w(
         name: str, row_count: int = DEFAULT_B4W_ROWS, **kwargs: Any
     ) -> Session:
+        if "Id1" in kwargs:
+            raise ValueError(
+                "Id1 is set per row (1..row_count) by populated_db_b4w and "
+                "cannot be overridden via **kwargs"
+            )
         session = db_session_factory(name)
         for i in range(row_count):
             row_kwargs = {k: (v() if callable(v) else v) for k, v in kwargs.items()}

tests/test_smoke_b4w.py

@@ -2,13 +2,22 @@ from datetime import date
 
 import faker
 
-the_faker = faker.Faker()
+from src.models.b4w import B4wDb
 
 
 def test_b4w_populate(populated_db_b4w):
+    val_dt_min, val_dt_max = date(2026, 1, 1), date(2026, 3, 31)
     session = populated_db_b4w(
         "b4w_basic",
         100,
-        ValDt=lambda: faker.Faker().date_between(date(2026, 1, 1), date(2026, 3, 31)),
+        ValDt=lambda: faker.Faker().date_between(val_dt_min, val_dt_max),
     )
     assert session
+    assert session.query(B4wDb).count() == 100
+    # ``ValDt`` was given as a per-row callable: it must have been resolved
+    # and persisted for every row.
+    dates = [d for (d,) in session.query(B4wDb.date_valid).all()]
+    assert all(val_dt_min <= d <= val_dt_max for d in dates)
+    # ``Id1`` is assigned per row: one distinct row per id, no dedup collisions.
+    ids = [i for (i,) in session.query(B4wDb.id_b4w).order_by(B4wDb.id_b4w).all()]
+    assert ids == list(range(1, 101))