AbortTransition accepts a singlep param

coaster/sqlalchemy/statemanager.py

@@ -73,7 +73,7 @@ def publish(self):
             # success, message = post.publish()
 
             success = False
-            message = "A transition is not desireable right now"
+            message = "A transition is not desirable right now"
             raise AbortTransition(success, message)
 
             # Any other exception will be raised
@@ -245,10 +245,11 @@ class StateTransitionError(BadRequest, TypeError):
 class AbortTransition(Exception):
     """
     Transitions may raise AbortTransition to return without changing state.
-    The parameters to the exception are returned as the transition’s result.
+    Accepts a single parameter `message` which is returned as the transition’s result.
+    Despite the name, `message` can be of any data type.
     """
-    pass
-
+    def __init__(self, message=None):
+        self.message = message
 
 # --- Classes -----------------------------------------------------------------
 
@@ -548,7 +549,7 @@ def __call__(self, *args, **kwargs):
             result = self.statetransition.func(self.obj, *args, **kwargs)
         except AbortTransition as e:
             transition_exception.send(self.obj, transition=self.statetransition, exception=e)
-            return None if len(e.args) == 0 else e.args[0] if len(e.args) == 1 else e.args
+            return e.message
         except Exception as e:
             transition_exception.send(self.obj, transition=self.statetransition, exception=e)
             raise

tests/test_statemanager.py

@@ -125,8 +125,8 @@ def abort(self, success=False, empty_abort=False):
             if empty_abort:
                 raise AbortTransition()
             else:
-                raise AbortTransition(success)
-        return success
+                raise AbortTransition((success, 'failed'))
+        return success, 'passed'
 
     @with_roles(call={'author'})
     @state.transition(state.PUBLISHED, state.PENDING)
@@ -535,16 +535,18 @@ def test_transition_aborterror(self):
         self.post.submit()  # This is to set an initial state for this test
         self.assertTrue(self.post.state.PENDING)
 
-        success = self.post.abort(success=False)
+        success, message = self.post.abort(success=False)
         self.assertEqual(success, False)
+        self.assertEqual(message, "failed")
         self.assertTrue(self.post.state.PENDING)  # state wont change
 
         success = self.post.abort(success=False, empty_abort=True)
         self.assertEqual(success, None)
         self.assertTrue(self.post.state.PENDING)  # state wont change
 
-        success = self.post.abort(success=True)
+        success, message = self.post.abort(success=True)
         self.assertEqual(success, True)
+        self.assertEqual(message, 'passed')
         self.assertTrue(self.post.state.PUBLISHED)  # state will change
 
         with self.assertRaises(RandomException):