From bc378d091b6eb6a55b0230d7c007896bf76bbd4d Mon Sep 17 00:00:00 2001
From: Adam Vandenberg <flangy@gmail.com>
Date: Thu, 12 Nov 2009 11:09:20 -0800
Subject: [PATCH] Compare against HOMEBREW_CELLAR using real paths.

The code in Keg.self.for path uses "path = path.parent.realpath" to walk
up subfolders looking for a Keg.

Because 'realpath' is in there, and the path is checked against
HOMEBREW_CELLAR, which  may be a symlink, we need to do realpath-to-realpath
comparisons in Keg. Otherwise, we will hit equivalent but symlinked folders,
not see that they are the same, and walk all the way up to / and then
error out.
---
 Library/Homebrew/keg.rb | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Library/Homebrew/keg.rb b/Library/Homebrew/keg.rb
index b9ca83953a..8fdc78b4ec 100644
--- a/Library/Homebrew/keg.rb
+++ b/Library/Homebrew/keg.rb
@@ -24,14 +24,15 @@
 class Keg <Pathname
   def initialize path
     super path
-    raise "#{to_s} is not a valid keg" unless parent.parent == HOMEBREW_CELLAR
+    raise "#{to_s} is not a valid keg" unless parent.parent.realpath == HOMEBREW_CELLAR.realpath
     raise "#{to_s} is not a directory" unless directory?
   end
 
   # if path is a file in a keg then this will return the containing Keg object
   def self.for path
+    path = path.realpath
     while not path.root?
-      return Keg.new(path) if path.parent.parent == HOMEBREW_CELLAR
+      return Keg.new(path) if path.parent.parent == HOMEBREW_CELLAR.realpath
       path = path.parent.realpath # realpath() prevents root? failing
     end
     raise "#{path} is not inside a keg"