Vagrant::Env sets up the home directory (specified in config) with proper subfolders if they don't exist.

lib/vagrant/env.rb

@@ -1,6 +1,7 @@
 module Vagrant
   class Env
     ROOTFILE_NAME = "Vagrantfile"
+    HOME_SUBDIRS = ["tmp", "boxes"]
 
     # Initialize class variables used
     @@persisted_vm = nil
@@ -16,6 +17,7 @@ module Vagrant
       def load!
         load_root_path!
         load_config!
+        load_home_directory!
         load_vm!
       end
 
@@ -34,6 +36,20 @@ module Vagrant
         Config.execute!
       end
 
+      def load_home_directory!
+        home_dir = File.expand_path(Vagrant.config.vagrant.home)
+
+        dirs = HOME_SUBDIRS.collect { |path| File.join(home_dir, path) }
+        dirs.unshift(home_dir)
+
+        dirs.each do |dir|
+          next if File.directory?(dir)
+
+          logger.info "Creating home directory since it doesn't exist: #{dir}"
+          FileUtils.mkdir_p(dir)
+        end
+      end
+
       def load_vm!
         File.open(dotfile_path) do |f|
           @@persisted_vm = Vagrant::VM.find(f.read)

test/vagrant/env_test.rb

@@ -27,6 +27,31 @@ class EnvTest < Test::Unit::TestCase
     end
   end
 
+  context "loading home directory" do
+    setup do
+      @home_dir = File.expand_path(Vagrant.config.vagrant.home)
+
+      File.stubs(:directory?).returns(true)
+      FileUtils.stubs(:mkdir_p)
+    end
+
+    should "create each directory if it doesn't exist" do
+      create_seq = sequence("create_seq")
+      File.stubs(:directory?).returns(false)
+      Vagrant::Env::HOME_SUBDIRS.each do |subdir|
+        FileUtils.expects(:mkdir_p).with(File.join(@home_dir, subdir)).in_sequence(create_seq)
+      end
+
+      Vagrant::Env.load_home_directory!
+    end
+
+    should "not create directories if they exist" do
+      File.stubs(:directory?).returns(true)
+      FileUtils.expects(:mkdir_p).never
+      Vagrant::Env.load_home_directory!
+    end
+  end
+
   context "loading config" do
     setup do
       @root_path = "/foo"
@@ -69,6 +94,7 @@ class EnvTest < Test::Unit::TestCase
       Vagrant::Env.expects(:load_config!).once
       Vagrant::Env.expects(:load_vm!).once
       Vagrant::Env.expects(:load_root_path!).once
+      Vagrant::Env.expects(:load_home_directory!).once
       Vagrant::Env.load!
     end
   end