fix: Regression on 2.3.2 that broke Enum support (#458)

* fix: Regression on 2.3.2 that broke Enum support

Author: fgmacedo

statemachine/states.py

@@ -54,7 +54,6 @@ def __eq__(self, other):
         return list(self) == list(other)
 
     def __getattr__(self, name: str):
-        name = name.lower()
         if name in self._states:
             return self._states[name]
         raise AttributeError(f"{name} not found in {self.__class__.__name__}")
@@ -81,7 +80,7 @@ def items(self):
         return self._states.items()
 
     @classmethod
-    def from_enum(cls, enum_type: EnumType, initial, final=None):
+    def from_enum(cls, enum_type: EnumType, initial, final=None, use_enum_instance: bool = False):
         """
         Creates a new instance of the ``States`` class from an enumeration.
 
@@ -125,20 +124,37 @@ def from_enum(cls, enum_type: EnumType, initial, final=None):
         True
 
         >>> sm.current_state_value
+        2
+
+        If you need to use the enum instance as the state value, you can set the
+        ``use_enum_instance=True``:
+
+        >>> states = States.from_enum(Status, initial=Status.pending, use_enum_instance=True)
+        >>> states.completed.value
         <Status.completed: 2>
 
+        .. deprecated:: 2.3.3
+
+            On the next major release, the ``use_enum_instance=True`` will be the default.
+
         Args:
             enum_type: An enumeration containing the states of the machine.
             initial: The initial state of the machine.
             final: A set of final states of the machine.
+            use_enum_instance: If ``True``, the value of the state will be the enum item instance,
+                otherwise the enum item value.
 
         Returns:
             A new instance of the :ref:`States (class)`.
         """
         final_set = set(ensure_iterable(final))
         return cls(
             {
-                e.name.lower(): State(value=e, initial=e is initial, final=e in final_set)
+                e.name: State(
+                    value=(e if use_enum_instance else e.value),
+                    initial=e is initial,
+                    final=e in final_set,
+                )
                 for e in enum_type
             }
         )

tests/django_project/workflow/statemachines.py

@@ -7,8 +7,8 @@
 class WorfklowStateMachine(StateMachine):
     _ = States.from_enum(WorkflowSteps, initial=WorkflowSteps.DRAFT, final=WorkflowSteps.PUBLISHED)
 
-    publish = _.draft.to(_.published, cond="is_active")
-    notify_user = _.draft.to.itself(internal=True, cond="has_user")
+    publish = _.DRAFT.to(_.PUBLISHED, cond="is_active")
+    notify_user = _.DRAFT.to.itself(internal=True, cond="has_user")
 
     def has_user(self):
         return bool(self.model.user)

tests/examples/enum_campaign_machine.py

@@ -14,34 +14,37 @@
 
 
 class CampaignStatus(Enum):
-    draft = 1
-    producing = 2
-    closed = 3
+    DRAFT = 1
+    PRODUCING = 2
+    CLOSED = 3
 
 
 class CampaignMachine(StateMachine):
     "A workflow machine"
 
     states = States.from_enum(
-        CampaignStatus, initial=CampaignStatus.draft, final=CampaignStatus.closed
+        CampaignStatus,
+        initial=CampaignStatus.DRAFT,
+        final=CampaignStatus.CLOSED,
+        use_enum_instance=True,
     )
 
-    add_job = states.draft.to(states.draft) | states.producing.to(states.producing)
-    produce = states.draft.to(states.producing)
-    deliver = states.producing.to(states.closed)
+    add_job = states.DRAFT.to(states.DRAFT) | states.PRODUCING.to(states.PRODUCING)
+    produce = states.DRAFT.to(states.PRODUCING)
+    deliver = states.PRODUCING.to(states.CLOSED)
 
 
 # %%
 # Asserting campaign machine declaration
 
-assert CampaignMachine.draft.initial
-assert not CampaignMachine.draft.final
+assert CampaignMachine.DRAFT.initial
+assert not CampaignMachine.DRAFT.final
 
-assert not CampaignMachine.producing.initial
-assert not CampaignMachine.producing.final
+assert not CampaignMachine.PRODUCING.initial
+assert not CampaignMachine.PRODUCING.final
 
-assert not CampaignMachine.closed.initial
-assert CampaignMachine.closed.final
+assert not CampaignMachine.CLOSED.initial
+assert CampaignMachine.CLOSED.final
 
 
 # %%
@@ -50,8 +53,8 @@ class CampaignMachine(StateMachine):
 sm = CampaignMachine()
 res = sm.send("produce")
 
-assert sm.draft.is_active is False
-assert sm.producing.is_active is True
-assert sm.closed.is_active is False
-assert sm.current_state == sm.producing
-assert sm.current_state_value == CampaignStatus.producing
+assert sm.DRAFT.is_active is False
+assert sm.PRODUCING.is_active is True
+assert sm.CLOSED.is_active is False
+assert sm.current_state == sm.PRODUCING
+assert sm.current_state_value == CampaignStatus.PRODUCING