feature complete version, tests and debug pending

test/test_mealy.py

@@ -7,4 +7,15 @@ class TestMachine(unittest.TestCase):
 
     def test_init(self):
         m = Machine()
-        self.assertIsNotNone(m)
+        self.assertIsNotNone(m)
+
+    def test_add_state_two_start_states(self):
+        m = Machine()
+        m.add_state("A", {}, True, False)
+        self.assertRaises(ValueError, m.add_state, "B", {}, True, False)
+
+    def test_add_two_end_states(self):
+        m = Machine()
+        m.add_state("A", {}, True, False)
+        m.add_state("B", {}, False, True)
+        m.add_state("C", {}, False, True)