Hook#apply

lib/vagrant/action/hook.rb

@@ -64,6 +64,40 @@ module Vagrant
       def prepend(new)
         @prepend_hooks << new
       end
+
+      # This applies the given hook to a builder. This should not be
+      # called directly.
+      #
+      # @param [Builder] builder
+      def apply(builder)
+        # Prepends first
+        @prepend_hooks.each do |klass|
+          builder.insert(0, klass)
+        end
+
+        # Appends
+        @append_hooks.each do |klass|
+          builder.use(klass)
+        end
+
+        # Before hooks
+        @before_hooks.each do |key, list|
+          next if !builder.index(key)
+
+          list.each do |klass|
+            builder.insert_before(key, klass)
+          end
+        end
+
+        # After hooks
+        @after_hooks.each do |key, list|
+          next if !builder.index(key)
+
+          list.each do |klass|
+            builder.insert_after(key, klass)
+          end
+        end
+      end
     end
   end
 end

test/unit/vagrant/action/hook_test.rb

@@ -1,5 +1,6 @@
 require File.expand_path("../../../base", __FILE__)
 
+require "vagrant/action/builder"
 require "vagrant/action/hook"
 
 describe Vagrant::Action::Hook do
@@ -49,4 +50,19 @@ describe Vagrant::Action::Hook do
       subject.prepend_hooks.should == [1, 2]
     end
   end
+
+  describe "applying" do
+    let(:builder) { Vagrant::Action::Builder.new }
+
+    it "should build the proper stack" do
+      subject.prepend("1")
+      subject.append("9")
+      subject.after("1", "2")
+      subject.before("9", "8")
+
+      subject.apply(builder)
+
+      builder.stack.map(&:first).should == %w[1 2 8 9]
+    end
+  end
 end