Only calculate the target VMs once

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

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

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 })