From 863c83a0f525d877fc2a66236600f7247eb648a6 Mon Sep 17 00:00:00 2001
From: Xu Cheng <xucheng@me.com>
Date: Sun, 29 Nov 2015 15:37:06 +0800
Subject: [PATCH] upgrade: use installed_kegs

---
 Library/Homebrew/cmd/upgrade.rb | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Library/Homebrew/cmd/upgrade.rb b/Library/Homebrew/cmd/upgrade.rb
index 83c34340f3..9c71d40571 100644
--- a/Library/Homebrew/cmd/upgrade.rb
+++ b/Library/Homebrew/cmd/upgrade.rb
@@ -14,8 +14,9 @@ module Homebrew
       outdated = ARGV.resolved_formulae.select(&:outdated?)
 
       (ARGV.resolved_formulae - outdated).each do |f|
-        if f.rack.directory?
-          version = f.rack.subdirs.map { |d| Keg.new(d).version }.max
+        versions = f.installed_kegs.map { |keg| keg.version }
+        if versions.any?
+          version = versions.max
           onoe "#{f.full_name} #{version} already installed"
         else
           onoe "#{f.full_name} not installed"