replaced redundant code in a few places w/ new identify_prefix() helper

2 files changed, 13 insertions, 1 deletions

diff --git a/passlib/utils/__init__.py b/passlib/utils/__init__.py
index 4b75a53..ffbc60f 100644
--- a/passlib/utils/__init__.py
+++ b/passlib/utils/__init__.py
@@ -6,7 +6,7 @@
 from base64 import b64encode, b64decode
 from codecs import lookup as _lookup_codec
 from cStringIO import StringIO
-from functools import update_wrapper
+##from functools import update_wrapper
 from hashlib import sha256
 import logging; log = logging.getLogger(__name__)
 from math import log as logb
diff --git a/passlib/utils/handlers.py b/passlib/utils/handlers.py
index cfa9381..8d23200 100644
--- a/passlib/utils/handlers.py
+++ b/passlib/utils/handlers.py
@@ -60,6 +60,18 @@ def identify_regexp(hash, pat):
             return False
     return pat.match(hash) is not None
 
+def identify_prefix(hash, prefix):
+    "identify() helper for matching against prefixes"
+    #NOTE: prefix may be a tuple of strings (since startswith supports that)
+    if not hash:
+        return False
+    if isinstance(hash, bytes):
+        try:
+            hash = hash.decode("ascii")
+        except UnicodeDecodeError:
+            return False
+    return hash.startswith(prefix) 
+
 #=========================================================
 #parsing helpers
 #=========================================================