# HG changeset patch
# User Idan Kamara <idankk86@gmail.com>
# Date 2012-11-12 17:27:03
# Node ID 1e6b5faf9d4ecc3022e207135e742468467c9b8f
# Parent  7f5dab94e48cea28a1a7c6a296d7c07eed5d1db7

grep: don't search past the end of the searched string

'*' causes the resulting RE to match 0 or more repetitions of the preceding RE:

>>> bool(re.search('.*', ''))
>>> True

This causes an infinite loop because currently we're only checking if there was
a match without looking at where we are in the searched string.

diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -2936,7 +2936,7 @@ def grep(ui, repo, pattern, *pats, **opt
     def matchlines(body):
         begin = 0
         linenum = 0
-        while True:
+        while True and begin < len(body):
             match = regexp.search(body, begin)
             if not match:
                 break
diff --git a/tests/test-grep.t b/tests/test-grep.t
--- a/tests/test-grep.t
+++ b/tests/test-grep.t
@@ -23,6 +23,10 @@ pattern error
 
 simple
 
+  $ hg grep '.*'
+  port:4:export
+  port:4:vaportight
+  port:4:import/export
   $ hg grep port port
   port:4:export
   port:4:vaportight