tool/merger.rb: Guard match failure properly

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67694 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 1 deletions

diff --git a/tool/merger.rb b/tool/merger.rb
index 33d663c3cc..4f21e81eb7 100755
--- a/tool/merger.rb
+++ b/tool/merger.rb
@@ -259,7 +259,7 @@ else
       end
       patch = resp.body
 
-      message = "\n\n#{(patch.match(/^Subject: (.*)\n\ndiff --git/m)[1] || "Message not found for revision: #{git_rev}\n")}"
+      message = "\n\n#{(patch.match(/^Subject: (.*)\n\ndiff --git/m)&.[](1) || "Message not found for revision: #{git_rev}\n")}"
       puts "+ git apply"
       IO.popen(['git', 'apply'], 'w') { |f| f.write(patch) }
     else