# HG changeset patch
# User Matt Mackall <mpm@selenic.com>
# Date 1276900453 18000
# Node ID e5a2134c083b223bd2998b6694e430e4999caee3
# Parent  c040847539905c3f9c8b417586128695c72f3dd4
revset: nicer exception for empty queries

diff -r c04084753990 -r e5a2134c083b mercurial/revset.py
--- a/mercurial/revset.py	Fri Jun 18 21:35:21 2010 +0200
+++ b/mercurial/revset.py	Fri Jun 18 17:34:13 2010 -0500
@@ -546,6 +546,8 @@
 parse = parser.parser(tokenize, elements).parse
 
 def match(spec):
+    if not spec:
+        raise error.ParseError(_("empty query"))
     tree = parse(spec)
     weight, tree = optimize(tree, True)
     def mfunc(repo, subset):