This fixes #215

State instances passed to `initial` parameter of `Machine` constructor
had not been processed properly

Author: aleneum

Changelog.md

@@ -5,6 +5,7 @@
 - Bug #214: `LockedMachine` as a model prevented correct addition of `on_enter/exit_<state>` (thanks to @kr2)
 - Bug #217: Filtering rules for auto transitions in graphs falsely filtered certain transitions (thanks to @KarolOlko)
 - Bug #218: Uninitialized `EventData.transition` caused `AttributeError` in `EventData.__repr__` (thanks to @kunalbhagawati)
+- Bug #215: State instances passed to `initial` parameter of `Machine` constructor had not been processed properly (thanks @mathiasimmer)
 
 ## 0.5.2 (April, 2017)
 

tests/test_core.py

@@ -113,6 +113,10 @@ def test_pass_state_instances_instead_of_names(self):
         state_B2 = State('B', on_enter='this_passes')
         with self.assertRaises(ValueError):
             m.add_transition('advance2', state_A, state_B2)
+        m2 = Machine(states=states, initial=state_A.name)
+        assert m.initial == m2.initial
+        with self.assertRaises(ValueError):
+            Machine(states=states, initial=State('A'))
 
     def test_conditions(self):
         s = self.stuff

transitions/core.py

@@ -357,7 +357,7 @@ def __init__(self, model='self', states=None, initial='initial', transitions=Non
             states (list): A list of valid states. Each element can be either a
                 string or a State instance. If string, a new generic State
                 instance will be created that has the same name as the string.
-            initial (string): The initial state of the Machine.
+            initial (string or State): The initial state of the Machine.
             transitions (list): An optional list of transitions. Each element
                 is a dictionary of named arguments to be passed onto the
                 Transition initializer.
@@ -408,6 +408,7 @@ def __init__(self, model='self', states=None, initial='initial', transitions=Non
         self._after_state_change = []
         self._prepare_event = []
         self._finalize_event = []
+        self._initial = None
 
         self.states = OrderedDict()
         self.events = {}
@@ -447,9 +448,16 @@ def __init__(self, model='self', states=None, initial='initial', transitions=Non
             self.add_states(states)
 
         if initial is not None:
-            if initial not in self.states:
-                self.add_states(initial)
-        self._initial = initial
+            if isinstance(initial, State):
+                if initial.name not in self.states:
+                    self.add_state(initial)
+                else:
+                    assert self._has_state(initial)
+                self._initial = initial.name
+            else:
+                if initial not in self.states:
+                    self.add_state(initial)
+                self._initial = initial
 
         if transitions is not None:
             transitions = listify(transitions)