VM definition blocks are now stackable. [closes GH-94]

lib/vagrant/config.rb

@@ -98,6 +98,16 @@ module Vagrant
       attr_accessor :shared_folder_gid
       attr_accessor :system
 
+      # Represents a SubVM. This class is only used here in the VMs
+      # hash.
+      class SubVM
+        include Util::StackedProcRunner
+
+        def options
+          @options ||= {}
+        end
+      end
+
       def initialize
         @forwarded_ports = {}
         @shared_folders = {}
@@ -170,7 +180,9 @@ module Vagrant
 
       def define(name, options=nil, &block)
         options ||= {}
-        defined_vms[name.to_sym] = options.merge({:config_proc => block})
+        defined_vms[name.to_sym] ||= SubVM.new
+        defined_vms[name.to_sym].options.merge!(options)
+        defined_vms[name.to_sym].push_proc(&block)
       end
 
       def shift(orig, rsync)

lib/vagrant/environment.rb

@@ -106,8 +106,8 @@ module Vagrant
       return vms.values.first if !multivm?
       return parent.primary_vm if parent
 
-      config.vm.defined_vms.each do |name, options|
-        return vms[name] if options[:primary]
+      config.vm.defined_vms.each do |name, subvm|
+        return vms[name] if subvm.options[:primary]
       end
 
       nil
@@ -178,10 +178,13 @@ module Vagrant
       # If this environment represents some VM in a multi-VM environment,
       # we push that VM's configuration onto the config_queue.
       if vm_name
-        vm_data = parent.config.vm.defined_vms[vm_name] || {}
-        config_queue << vm_data[:config_proc]
+        subvm = parent.config.vm.defined_vms[vm_name]
+        config_queue << subvm.proc_stack if subvm
       end
 
+      # Flatten the config queue so any nested procs are flattened
+      config_queue.flatten!
+
       # Clear out the old data
       Config.reset!(self)
 

test/vagrant/config_test.rb

@@ -232,12 +232,12 @@ class ConfigTest < Test::Unit::TestCase
 
         proc = Proc.new { foo.call }
         @config.define(:name, &proc)
-        assert_equal proc, @config.defined_vms[:name][:config_proc]
+        assert @config.defined_vms[:name].proc_stack.include?(proc)
       end
 
       should "store the options" do
         @config.define(:name, :set => true)
-        assert @config.defined_vms[:name][:set]
+        assert @config.defined_vms[:name].options[:set]
       end
 
       should "not have multi-VMs by default" do