# HG changeset patch
# User Brian Neal <bgneal@gmail.com>
# Date 1392582684 21600
# Node ID 9c90ca37c023bd28cc7b72d3b3c4c7a40da30632
# Parent  6408a3f67d25a60abff3be28bae3eb3fbb75070d
No need to create a new set to handle a garble on encrypt.

diff -r 6408a3f67d25 -r 9c90ca37c023 purple/machine.py
--- a/purple/machine.py	Sun Feb 16 14:30:57 2014 -0600
+++ b/purple/machine.py	Sun Feb 16 14:31:24 2014 -0600
@@ -1,4 +1,4 @@
-# Copyright (C) 2013 by Brian Neal.
+# Copyright (C) 2013 - 2014 by Brian Neal.
 # This file is part of purple, the PURPLE (Cipher Machine 97) simulation.
 # purple is released under the MIT License (see LICENSE.txt).
 
@@ -30,7 +30,6 @@
 
     """
     VALID_KEYS = set(string.ascii_uppercase)
-    VALID_DECRYPT_KEYS = set(string.ascii_uppercase + '-')
     STRAIGHT_PLUGBOARD = 'AEIOUYBCDFGHJKLMNPQRSTVWXZ'
 
     def __init__(self, switches_pos=None, fast_switch=1, middle_switch=2,
@@ -186,8 +185,6 @@
         """
         plaintext = []
         for i, c in enumerate(ciphertext):
-            if c not in self.VALID_DECRYPT_KEYS:
-                raise Purple97Error("invalid input '{}' to decrypt".format(c))
 
             # Process a garble:
             if c == '-':
@@ -195,6 +192,9 @@
                 self.step()
                 continue
 
+            if c not in self.VALID_KEYS:
+                raise Purple97Error("invalid input '{}' to decrypt".format(c))
+
             n = self.plugboard[c]
 
             if n < 6: