Add next state advancer

CHANGELOG

@@ -1,3 +1,5 @@
+- 0.0.14
+	* Add next state advancer
 - 0.0.13
 	* Add next state peek
 - 0.0.12

setup.cfg

@@ -1,6 +1,6 @@
 [metadata]
 name = shep
-version = 0.0.13
+version = 0.0.14
 description = Multi-state key stores using bit masks
 author = Louis Holbrook
 author_email = dev@holbrook.no

shep/persist.py

@@ -58,11 +58,14 @@ class PersistedState(State):
 
     def move(self, key, to_state):
         from_state = self.state(key)
-        k_from = self.name(from_state)
-
         to_state = super(PersistedState, self).move(key, to_state)
+        return self.__movestore(key, from_state, to_state)
 
+
+    def __movestore(self, key, from_state, to_state):
+        k_from = self.name(from_state)
         k_to = self.name(to_state)
+
         self.__ensure_store(k_to)
 
         contents = self.__stores[k_from].get(key)
@@ -96,3 +99,9 @@ class PersistedState(State):
         k = self.name(state)
 
         return self.__stores[k].path(key=key)
+
+
+    def next(self, key=None):
+        from_state = self.state(key)
+        to_state = super(PersistedState, self).next(key)
+        return self.__movestore(key, from_state, to_state)

shep/state.py

@@ -132,8 +132,8 @@ class State:
 
 
     def name(self, v):
-        if v == None:
-            return self.NEW
+        if v == None or v == 0:
+            return 'NEW'
         k = self.__reverse.get(v)
         if k == None:
             raise StateInvalid(v)
@@ -269,6 +269,14 @@ class State:
         return self.__keys[state]
 
 
+    def sync(self, state):
+        pass
+
+
+    def path(self, state, key=None):
+        return None
+
+
     def peek(self, key):
         state = self.__keys_reverse.get(key)
         if state == None:
@@ -284,3 +292,9 @@ class State:
             raise StateInvalid('unknown state {}'.format(state))
 
         return state
+
+
+    def next(self, key):
+        from_state = self.state(key)
+        new_state = self.peek(key)
+        return self.__move(key, from_state, new_state)

shep/store/file.py

@@ -23,7 +23,7 @@ class SimpleFileStore:
                 raise FileExistsError(fp)
             if contents == None:
                 raise FileExistsError('will not overwrite empty content on existing file {}. Use rm then add instead'.format(fp))
-        elif contents == None:
+        if contents == None:
             contents = ''
 
         f = open(fp, 'w')

tests/test_file.py

@@ -145,7 +145,27 @@ class TestStateReport(unittest.TestCase):
         
         d = os.path.join(self.d, 'FOO', 'BAR')
         self.assertEqual(self.states.path(self.states.FOO, key='BAR'), d)
+
+
+    def test_next(self):
+        self.states.put('abcd')
+
+        self.states.next('abcd')
+        self.assertEqual(self.states.state('abcd'), self.states.FOO)
         
+        self.states.next('abcd')
+        self.assertEqual(self.states.state('abcd'), self.states.BAR)
+
+        with self.assertRaises(StateInvalid):
+            self.states.next('abcd')
+
+        fp = os.path.join(self.d, 'FOO', 'abcd')
+        with self.assertRaises(FileNotFoundError):
+            os.stat(fp)
+
+        fp = os.path.join(self.d, 'BAR', 'abcd')
+        os.stat(fp)
+
 
 if __name__ == '__main__':
     unittest.main()