US03-01: Aggregate Album Evidence (#61)

tests/characterization/test_pa_album.py

@@ -22,6 +22,19 @@ def test_webapp_album_of_mirrors_album_label():
         assert query.album_of(p, lib) == pa.album_label(Path(p), lib), p
 
 
+def test_albums_service_album_label_matches_donor():
+    # Parity: the extracted single implementation (US03-01) matches the donor rule
+    # (donor_ledger.yaml: pa-album-label, wa-album-of). The service takes a tuple of
+    # library roots; the donor takes one Path.
+    from photo_pipeline.services.albums import album_label
+
+    lib = Path("/lib")
+    for p in ("/lib/Urlaub/Rom/a.jpg", "/lib/a.jpg", "/other/x/a.jpg", "/lib/x/y/a.jpg"):
+        assert album_label(p, (lib,)) == pa.album_label(Path(p), lib), p
+    # No configured roots → bare parent name, like the donor with library=None.
+    assert album_label("/lib/x/a.jpg", ()) == pa.album_label(Path("/lib/x/a.jpg"), None)
+
+
 def test_fit_label_left_truncates():
     assert pa.fit_label("short", 10) == "short"
     assert pa.fit_label("Urlaub/Somewhere/Rom", 8) == "…ere/Rom"