Deconstruct empty list of required and uniqueness keyword arguments

This makes it consistent with base django field which deconstructs all
fields which are different to default arguments.

Additionally does it fix issues for custom fields which depend on
differentiating between required=None and required=[] like LocalizedField.

Author: Oliver Sauder

psqlextra/fields/hstore_field.py

@@ -1,8 +1,8 @@
 from typing import List, Tuple, Union
 
+from django.contrib.postgres.fields import HStoreField as DjangoHStoreField
 from django.db.models.expressions import Expression
 from django.db.models.fields import Field
-from django.contrib.postgres.fields import HStoreField as DjangoHStoreField
 
 from psqlextra.expressions import HStoreValue
 
@@ -59,10 +59,10 @@ def deconstruct(self):
         name, path, args, kwargs = super(
             HStoreField, self).deconstruct()
 
-        if self.uniqueness:
+        if self.uniqueness is not None:
             kwargs['uniqueness'] = self.uniqueness
 
-        if self.required:
+        if self.required is not None:
             kwargs['required'] = self.required
 
         return name, path, args, kwargs

tests/test_hstore_field.py

@@ -7,7 +7,7 @@ def test_deconstruct():
     """Tests whether the :see:HStoreField's deconstruct()
     method works properly."""
 
-    original_kwargs = dict(uniqueness=['beer', 'other'])
+    original_kwargs = dict(uniqueness=['beer', 'other'], required=[])
     _, _, _, new_kwargs = HStoreField(**original_kwargs).deconstruct()
 
     for key, value in original_kwargs.items():