Fix 'default and default_for_new' check (pynamodb#1170)

michaelstoops · Michael Stoops · web-flow · commit c84c8444bcea · 2023-03-30T14:37:55.000-04:00
Co-authored-by: Michael Stoops &lt;spam@michaelstoops.com&gt;
diff --git a/pynamodb/attributes.py b/pynamodb/attributes.py
@@ -111,7 +111,7 @@ def __init__(
         default_for_new: Optional[Union[Any, Callable[..., _T]]] = None,
         attr_name: Optional[str] = None,
     ) -> None:
-        if default and default_for_new:
+        if default is not None and default_for_new is not None:
             raise ValueError("An attribute cannot have both default and default_for_new parameters")
         if not callable(default) and not isinstance(default, _IMMUTABLE_TYPES):
             raise ValueError(
diff --git a/tests/test_attributes.py b/tests/test_attributes.py
@@ -147,6 +147,13 @@ def test_default(self):
         Attribute(default=list)
         Attribute(default_for_new=list)
 
+        with pytest.raises(ValueError, match="An attribute cannot have both default and default_for_new parameters"):
+            Attribute(default='test', default_for_new='test')
+
+        with pytest.raises(ValueError, match="An attribute cannot have both default and default_for_new parameters"):
+            Attribute(default=False, default_for_new='test')
+
+
 
 class TestUTCDateTimeAttribute:
     """
