From 61f01632c6b869965832dd56411c2b3ed2bb82ca Mon Sep 17 00:00:00 2001
From: Jack Nagel <jacknagel@gmail.com>
Date: Tue, 29 Jan 2013 10:25:07 -0600
Subject: [PATCH] Keg#lock: guard against nil in ensure

Fixes Homebrew/homebrew#17403.
---
 Library/Homebrew/keg.rb | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/Library/Homebrew/keg.rb b/Library/Homebrew/keg.rb
index 674ac881fa..ff249ed2e5 100644
--- a/Library/Homebrew/keg.rb
+++ b/Library/Homebrew/keg.rb
@@ -70,8 +70,10 @@ class Keg < Pathname
     end
     yield
   ensure
-    file.flock(File::LOCK_UN)
-    file.close
+    unless file.nil?
+      file.flock(File::LOCK_UN)
+      file.close
+    end
   end
 
   def linked_keg_record