--- a/scripts/generate-hg-s3-bundles
+++ b/scripts/generate-hg-s3-bundles
@@ -226,21 +226,18 @@ def generate_bundles(repo, upload=True, 
     gid = hg_stat.st_gid
 
     # Bundle files are named after the tip revision in the repository at
     # the time the bundle was created. This is the easiest way to name
     # bundle files.
     tip = subprocess.check_output([HG, '-R', repo_full, 'log', '-r', 'tip', '-T', '{node}'])
     print('tip is %s' % tip)
 
-    generaldelta = False
     with open(os.path.join(repo_full, '.hg', 'requires'), 'rb') as fh:
-        for line in fh:
-            if line.strip() == 'generaldelta':
-                generaldelta = True
+        generaldelta = 'generaldelta\n' in fh.readlines()
 
     bundle_path = os.path.join(BUNDLE_ROOT, repo)
 
     # Create directory to hold bundle files.
     try:
         os.makedirs(bundle_path, 0755)
     except OSError as e:
         if e.errno != errno.EEXIST: