From 739881b482bf3b7219a141ef9ec5b756d482b93a Mon Sep 17 00:00:00 2001
From: Mike McQuaid <mike@mikemcquaid.com>
Date: Tue, 16 Aug 2016 14:31:50 +0100
Subject: [PATCH] diagnostic: don't barf if HEAD is also a file.

Closes #694.
---
 Library/Homebrew/diagnostic.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Library/Homebrew/diagnostic.rb b/Library/Homebrew/diagnostic.rb
index 5d83c4b5a3..a0c6dcd210 100644
--- a/Library/Homebrew/diagnostic.rb
+++ b/Library/Homebrew/diagnostic.rb
@@ -1010,7 +1010,7 @@ module Homebrew
         return unless Utils.git_available?
 
         timestamp = if File.directory?("#{HOMEBREW_REPOSITORY}/.git")
-          HOMEBREW_REPOSITORY.cd { `git log -1 --format="%ct" HEAD`.to_i }
+          HOMEBREW_REPOSITORY.cd { `git log -1 --format="%ct" HEAD --`.to_i }
         else
           HOMEBREW_LIBRARY.mtime.to_i
         end