diff --git a/mercurial/util.py b/mercurial/util.py
--- a/mercurial/util.py
+++ b/mercurial/util.py
@@ -128,10 +128,12 @@ def binary(s):
 def unique(g):
     """return the uniq elements of iterable g"""
     seen = {}
+    l = []
     for f in g:
         if f not in seen:
             seen[f] = 1
-            yield f
+            l.append(f)
+    return l
 
 class Abort(Exception):
     """Raised if a command needs to print an error and exit."""