TEST: Test for #82 (merge_entities with missing list datatype)

unittests/test_apiutils.py

@@ -559,3 +559,17 @@ B: something else"""
     assert recA.get_property("propA").unit == "cm"
     # unchanged
     assert recB.get_property("propA").unit == "cm"
+
+
+def test_merge_missing_list_datatype_82():
+    """Merging two properties, where the list-valued one has no datatype."""
+
+    recA = db.Record().add_property("a", 5, datatype="B")
+    recB_with_DT = db.Record().add_property("a", [1, 2], datatype=f"LIST<{db.DOUBLE}>")
+    merge_entities(recA, recB_with_DT, force=True)
+    assert recA.get_property("a").datatype == f"LIST<{db.DOUBLE}>"
+
+    recA = db.Record().add_property("a", 5, datatype="B")
+    recB_without_DT = db.Record().add_property("a", [1, 2])
+    merge_entities(recA, recB_without_DT, force=True)
+    assert recA.get_property("a").datatype == "LIST<B>"