From 4c10eaf33243e1af956905acb8035a4fa51d4cac Mon Sep 17 00:00:00 2001
From: Camillo Lugaresi <camillo.lugaresi@gmail.com>
Date: Fri, 8 Jun 2012 04:24:50 +0200
Subject: [PATCH] Add depends_on :libpng as an alias to :x11

Some formulae ask for the x11 environment with ENV.libpng; mirror this
in the new dependency form.
---
 Library/Homebrew/dependencies.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Library/Homebrew/dependencies.rb b/Library/Homebrew/dependencies.rb
index 5164058d04..8b056f4ae7 100644
--- a/Library/Homebrew/dependencies.rb
+++ b/Library/Homebrew/dependencies.rb
@@ -29,7 +29,7 @@ class DependencyCollector
     spec, tag = spec.shift if spec.is_a? Hash
 
     dep = case spec
-    when :x11
+    when :x11, :libpng
       X11Dependency.new(tag)
     when String
       if LANGUAGE_MODULES.include? tag