[PATCH] templater.firstline should handle empty strings

[Brendan Cully]

# HG changeset patch
# User Brendan Cully <brendan at kublai.com>
# Node ID 77955f4f89b7d5e715a443767d4d43c1e614a3dc
# Parent  b73552a00b209c8fcd71fd23fb990c5d05910010
templater.firstline should handle empty strings

diff -r b73552a00b20 -r 77955f4f89b7 mercurial/templater.py
--- a/mercurial/templater.py	Mon Jun 26 16:47:24 2006 +0200
+++ b/mercurial/templater.py	Tue Jul 04 15:10:23 2006 -0700
@@ -221,6 +221,13 @@ def fill(text, width):
         fp.write(rest)
     return fp.getvalue()
 
+def firstline(text):
+    '''return the first line of text'''
+    try:
+        return text.splitlines(1)[0].rstrip('\r\n')
+    except IndexError:
+        return ''
+
 def isodate(date):
     '''turn a (timestamp, tzoff) tuple into an iso 8631 date and time.'''
     return util.datestr(date, format='%Y-%m-%d %H:%M')
@@ -280,7 +287,7 @@ common_filters = {
     "escape": lambda x: cgi.escape(x, True),
     "fill68": lambda x: fill(x, width=68),
     "fill76": lambda x: fill(x, width=76),
-    "firstline": lambda x: x.splitlines(1)[0].rstrip('\r\n'),
+    "firstline": firstline,
     "tabindent": lambda x: indent(x, '\t'),
     "isodate": isodate,
     "obfuscate": obfuscate,