From 40c339e3490bbce04127e7c4f0e27037ba85d34a Mon Sep 17 00:00:00 2001
From: Adam Vandenberg <flangy@gmail.com>
Date: Tue, 29 Jan 2013 20:31:33 -0800
Subject: [PATCH] Require --force to link keg-only.

Closes Homebrew/homebrew#13349.
---
 Library/Homebrew/cmd/link.rb | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Library/Homebrew/cmd/link.rb b/Library/Homebrew/cmd/link.rb
index 6371c41de6..76a3b00f09 100644
--- a/Library/Homebrew/cmd/link.rb
+++ b/Library/Homebrew/cmd/link.rb
@@ -35,6 +35,13 @@ module Homebrew extend self
         next
       end
 
+      f = Formula.factory(keg.fname)
+      if f.keg_only? and not ARGV.force?
+        opoo "#{keg.fname} is keg-only and must be linked with --force"
+        puts "Note that doing so can interfere with building software."
+        next
+      end
+
       keg.lock do
         print "Linking #{keg}... " do
           puts "#{keg.link(mode)} symlinks created"