Add warning when multiple Field annotations have bene detected

lovasoa · Jun 18, 2024 · dbd909f · dbd909f
1 parent c19b563
commit dbd909f
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/marshmallow_dataclass/__init__.py b/marshmallow_dataclass/__init__.py
@@ -733,6 +733,11 @@ def _field_for_annotated_type(
             or isinstance(arg, marshmallow.fields.Field)
         ]
         if marshmallow_annotations:
+            if len(marshmallow_annotations) > 1:
+                warnings.warn(
+                    "Multiple marshmallow Field annotations found. Using the last one."
+                )
+
             field = marshmallow_annotations[-1]
             # Got a field instance, return as is. User must know what they're doing
             if isinstance(field, marshmallow.fields.Field):