Vagrant.configure and versioned configuration

Vagrant.configure is now how configuration is done in Vagrantfiles
(previously it was Vagrant::Config.run). This function takes a single
argument which is the version of configuration to use.

Various internals were updated for this new versioned configuration.

Note that multiple versions of configuration aren't yet used so aren't
fully supported by Vagrant, but the foundation is being set here.

lib/vagrant.rb

@@ -92,6 +92,18 @@ module Vagrant
     @source_root ||= Pathname.new(File.expand_path('../../', __FILE__))
   end
 
+  # Configure a Vagrant environment. The version specifies the version
+  # of the configuration that is expected by the block. The block, based
+  # on that version, configures the environment.
+  #
+  # Note that the block isn't run immediately. Instead, the configuration
+  # block is stored until later, and is run when an environment is loaded.
+  #
+  # @param [String] version Version of the configuration
+  def self.configure(version, &block)
+    Config.run(version, &block)
+  end
+
   # Returns a superclass to use when creating a plugin for Vagrant.
   # Given a specific version, this returns a proper superclass to use
   # to register plugins for that version.

lib/vagrant/config.rb

@@ -32,10 +32,10 @@ module Vagrant
     #
     # Note that the block is not run immediately. Instead, it's proc is stored
     # away for execution later.
-    def self.run(&block)
+    def self.run(version="1", &block)
       # Store it for later
       @last_procs ||= []
-      @last_procs << block
+      @last_procs << [version, block]
     end
 
     # This is a method which will yield to a block and will capture all

lib/vagrant/config/loader.rb

@@ -80,11 +80,10 @@ module Vagrant
         @load_order.each do |key|
           next if !@sources.has_key?(key)
 
-          @sources[key].each do |proc|
+          @sources[key].each do |version, proc|
             if !@config_cache.has_key?(proc)
               @logger.debug("Loading from: #{key} (evaluating)")
-              current = current_config_klass.load(proc)
-              @config_cache[proc] = current
+              @config_cache[proc] = current_config_klass.load(proc)
             else
               @logger.debug("Loading from: #{key} (cache)")
             end
@@ -105,7 +104,11 @@ module Vagrant
       # the configuration object and are expected to mutate this
       # configuration object.
       def procs_for_source(source)
-        return [source] if source.is_a?(Proc)
+        # If the source is just a proc, we assume it is for the latest
+        # version of the configuration. This may be an ill assumption,
+        # but it made building the initial version of multi-versioned
+        # configuration easy to support the old sub-VM stuff.
+        return [[Config::VERSIONS_ORDER.last, source]] if source.is_a?(Proc)
 
         # Assume all string sources are actually pathnames
         source = Pathname.new(source) if source.is_a?(String)

templates/commands/init/Vagrantfile.erb

@@ -1,7 +1,7 @@
 # -*- mode: ruby -*-
 # vi: set ft=ruby :
 
-Vagrant::Config.run do |config|
+Vagrant.configure("1") do |config|
   # All Vagrant configuration is done here. The most common configuration
   # options are documented and commented below. For a complete reference,
   # please see the online documentation at vagrantup.com.

test/unit/vagrant/config_test.rb

@@ -7,6 +7,31 @@ describe Vagrant::Config do
     end
   end
 
+  it "should capture calls to `Vagrant.configure`" do
+    receiver = double()
+
+    procs = described_class.capture_configures do
+      Vagrant.configure("1") do
+        receiver.one
+      end
+
+      Vagrant.configure("2") do
+        receiver.two
+      end
+    end
+
+    procs.should be_kind_of(Array)
+    procs.length.should == 2
+    procs[0][0].should == "1"
+    procs[1][0].should == "2"
+
+    # Verify the proper procs were captured
+    receiver.should_receive(:one).once.ordered
+    receiver.should_receive(:two).once.ordered
+    procs[0][1].call
+    procs[1][1].call
+  end
+
   it "should capture configuration procs" do
     receiver = double()
 
@@ -22,6 +47,20 @@ describe Vagrant::Config do
 
     # Verify that the proper proc was captured
     receiver.should_receive(:hello!).once
-    procs[0].call
+    procs[0][0].should == "1"
+    procs[0][1].call
+  end
+
+  it "should capture the proper version" do
+    procs = described_class.capture_configures do
+      described_class.run("1") {}
+      described_class.run("2") {}
+    end
+
+    # Verify the structure of the result
+    procs.should be_kind_of(Array)
+    procs.length.should == 2
+    procs[0][0].should == "1"
+    procs[1][0].should == "2"
   end
 end