Added global data hash to environment. "system"-wide data bag for vagrant

lib/vagrant/environment.rb

@@ -145,6 +145,16 @@ module Vagrant
       end
     end
 
+    # Loads on initial access and reads data from the global data store.
+    # The global data store is global to Vagrant everywhere (in every environment),
+    # so it can be used to store system-wide information. Note that "system-wide"
+    # typically means "for this user" since the location of the global data
+    # store is in the home directory.
+    def global_data
+      return parent.global_data if parent
+      @global_data ||= DataStore.new(File.expand_path("global_data.json", home_path))
+    end
+
     # Loads (on initial access) and reads data from the local data
     # store. This file is always at the root path as the file "~/.vagrant"
     # and contains a JSON dump of a hash. See {DataStore} for more

test/vagrant/environment_test.rb

@@ -245,6 +245,28 @@ class EnvironmentTest < Test::Unit::TestCase
     end
   end
 
+  context "global data" do
+    setup do
+      @env = mock_environment
+    end
+
+    should "lazy load the data store only once" do
+      result = mock("result")
+      Vagrant::DataStore.expects(:new).with(File.expand_path("global_data.json", @env.home_path)).returns(result).once
+      assert_equal result, @env.global_data
+      assert_equal result, @env.global_data
+      assert_equal result, @env.global_data
+    end
+
+    should "return the parent's local data if a parent exists" do
+      @env.stubs(:parent).returns(mock_environment)
+      result = @env.parent.global_data
+
+      Vagrant::DataStore.expects(:new).never
+      assert_equal result, @env.global_data
+    end
+  end
+
   context "loading logger" do
     should "lazy load the logger only once" do
       result = Vagrant::Util::ResourceLogger.new("vagrant", mock_environment)