add warning about auto to usage doc, fix CI

Author: bckohan

django_enum/tests/tests.py

@@ -1262,24 +1262,24 @@ def test_drf_serializer(self):
 
             class TestSerializer(serializers.ModelSerializer):
 
-                small_pos_int = EnumField(SmallPosIntEnum)
-                small_int = EnumField(SmallIntEnum)
-                pos_int = EnumField(PosIntEnum)
-                int = EnumField(IntEnum)
-                big_pos_int = EnumField(BigPosIntEnum)
-                big_int = EnumField(BigIntEnum)
-                constant = EnumField(Constants)
-                text = EnumField(TextEnum)
-                extern = EnumField(ExternEnum)
-                dj_int_enum = EnumField(DJIntEnum)
-                dj_text_enum = EnumField(DJTextEnum)
-                non_strict_int = EnumField(SmallPosIntEnum, strict=False)
+                small_pos_int = EnumField(self.SmallPosIntEnum)
+                small_int = EnumField(self.SmallIntEnum)
+                pos_int = EnumField(self.PosIntEnum)
+                int = EnumField(self.IntEnum)
+                big_pos_int = EnumField(self.BigPosIntEnum)
+                big_int = EnumField(self.BigIntEnum)
+                constant = EnumField(self.Constants)
+                text = EnumField(self.TextEnum)
+                extern = EnumField(self.ExternEnum)
+                dj_int_enum = EnumField(self.DJIntEnum)
+                dj_text_enum = EnumField(self.DJTextEnum)
+                non_strict_int = EnumField(self.SmallPosIntEnum, strict=False)
                 non_strict_text = EnumField(
-                    TextEnum,
+                    self.TextEnum,
                     strict=False,
                     allow_blank=True
                 )
-                no_coerce = EnumField(SmallPosIntEnum)
+                no_coerce = EnumField(self.SmallPosIntEnum)
 
                 class Meta:
                     model = EnumTester

doc/source/usage.rst

@@ -69,12 +69,14 @@ simple declarative syntax are possible with ``EnumField``. See
 External Enum Types
 ###################
 
-Externally defined, that is ``Enum`` classes defined externally to your code
-base or enum classes that otherwise do not inherit from Django's Choices type,
-are supported. When no choices are present on an ``Enum`` type, ``EnumField``
-will attempt to use the ``label`` member on each enumeration value if it is
-present, otherwise the labels will be based off the enumeration name. Choices
-can also be overridden at the ``EnumField`` declaration.
+``Enum`` classes defined externally to your code base or enum classes that
+otherwise do not inherit from Django's ``Choices`` type, are supported. When no
+choices are present on an ``Enum`` type, ``EnumField`` will attempt to use the
+``label`` member on each enumeration value if it is present, otherwise the
+labels will be based off the enumeration name. Choices can also be overridden
+at the ``EnumField`` declaration.
+
+In short, ``EnumField`` should work with any subclass of ``Enum``.
 
 .. code:: python
 
@@ -94,6 +96,17 @@ can also be overridden at the ``EnumField`` declaration.
 
 The above code will produce a choices set like ``[('V0', 'VALUE0'), ...]``.
 
+.. warning::
+
+    One nice feature of Django's ``Choices`` type is that it disables
+    ``auto()`` on ``Enum`` fields. ``auto()`` can be dangerous because the
+    values assigned depend on the order of declaration. This means that if the
+    order changes existing database values will no longer align with the
+    enumeration values. When using ``Enums`` where control over the values is
+    not certain it is a good idea to add integration tests that look for value
+    changes.
+
+
 Parameters
 ##########