diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -2935,7 +2935,7 @@ def grep(ui, repo, pattern, *pats, **opt
     def matchlines(body):
         begin = 0
         linenum = 0
-        while True and begin < len(body):
+        while begin < len(body):
             match = regexp.search(body, begin)
             if not match:
                 break