Hashlib doesn't take unicode.

pre_commit/store.py

@@ -1,6 +1,5 @@
 from __future__ import unicode_literals
 
-import hashlib
 import io
 import logging
 import os
@@ -11,6 +10,7 @@ from plumbum import local
 
 from pre_commit.prefixed_command_runner import PrefixedCommandRunner
 from pre_commit.util import clean_path_on_failure
+from pre_commit.util import hex_md5
 
 
 logger = logging.getLogger('pre_commit')
@@ -75,9 +75,7 @@ class Store(object):
         self.require_created()
 
         # Check if we already exist
-        sha_path = os.path.join(
-            self.directory, sha + '_' + hashlib.md5(url).hexdigest()
-        )
+        sha_path = os.path.join(self.directory, sha + '_' + hex_md5(url))
         if os.path.exists(sha_path):
             return os.readlink(sha_path)
 

pre_commit/util.py

@@ -2,6 +2,7 @@ from __future__ import unicode_literals
 
 import contextlib
 import functools
+import hashlib
 import os
 import os.path
 import shutil
@@ -56,3 +57,11 @@ def noop_context():
 
 def shell_escape(arg):
     return "'" + arg.replace("'", "'\"'\"'".strip()) + "'"
+
+
+def hex_md5(s):
+    """Hexdigest an md5 of the string.
+
+    :param text s:
+    """
+    return hashlib.md5(s.encode('utf-8')).hexdigest()