From ccad6af8cfa7724126f0f3747c20a4666051b8db Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Tue, 24 Aug 2010 17:50:41 -0700
Subject: [PATCH] Only calculate the target VMs once

---
 lib/vagrant/command/helpers.rb       | 20 +++++++++++---------
 lib/vagrant/command/status.rb        |  5 ++---
 test/vagrant/command/helpers_test.rb |  6 ++++++
 3 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/lib/vagrant/command/helpers.rb b/lib/vagrant/command/helpers.rb
index 36554ea91..d56640b6c 100644
--- a/lib/vagrant/command/helpers.rb
+++ b/lib/vagrant/command/helpers.rb
@@ -4,16 +4,18 @@ module Vagrant
       # This returns an array of {VM} objects depending on the arguments
       # given to the command.
       def target_vms
-        if env.multivm?
-          return env.vms if !self.name
-          vm = env.vms[self.name.to_sym]
-          raise VMNotFoundError.new("A VM by the name of `#{self.name}` was not found.") if !vm
-        else
-          raise MultiVMEnvironmentRequired.new("A multi-vm environment is required for name specification to a command.") if self.name
-          vm = env.vms.values.first
-        end
+        @target_vms ||= begin
+          if env.multivm?
+            return env.vms if !self.name
+            vm = env.vms[self.name.to_sym]
+            raise VMNotFoundError.new("A VM by the name of `#{self.name}` was not found.") if !vm
+          else
+            raise MultiVMEnvironmentRequired.new("A multi-vm environment is required for name specification to a command.") if self.name
+            vm = env.vms.values.first
+          end
 
-        [vm]
+          [vm]
+        end
       end
     end
   end
diff --git a/lib/vagrant/command/status.rb b/lib/vagrant/command/status.rb
index 5468de18e..7232ec7ed 100644
--- a/lib/vagrant/command/status.rb
+++ b/lib/vagrant/command/status.rb
@@ -10,9 +10,8 @@ module Vagrant
       end
 
       def route
-        vms = target_vms
-        show_multivm if vms.length > 1
-        show_single(vms.first)
+        show_multivm if target_vms.length > 1
+        show_single(target_vms.first)
       end
 
       protected
diff --git a/test/vagrant/command/helpers_test.rb b/test/vagrant/command/helpers_test.rb
index ece67bc30..606b269eb 100644
--- a/test/vagrant/command/helpers_test.rb
+++ b/test/vagrant/command/helpers_test.rb
@@ -17,6 +17,12 @@ class CommandHelpersTest < Test::Unit::TestCase
       @env = mock_environment
     end
 
+    should "only calculate the result once" do
+      instance = command([], @env)
+      result = instance.target_vms
+      assert instance.target_vms.equal?(result)
+    end
+
     context "without multivm" do
       setup do
         @env.stubs(:vms).returns({ :one => 1 })