Support refreshing the machine cache

lib/vagrant/environment.rb

@@ -217,14 +217,21 @@ module Vagrant
     #   Vagrantfile).
     # @param [Symbol] provider The provider that this machine should be
     #   backed by.
+    # @param [Boolean] refresh If true, then if there is a cached version
+    #   it is reloaded.
     # @return [Machine]
-    def machine(name, provider)
+    def machine(name, provider, refresh=false)
       @logger.info("Getting machine: #{name} (#{provider})")
 
       # Compose the cache key of the name and provider, and return from
       # the cache if we have that.
       cache_key = [name, provider]
       @machines ||= {}
+      if refresh
+        @logger.info("Refreshing machine (busting cache): #{name} (#{provider})")
+        @machines.delete(cache_key)
+      end
+
       if @machines.has_key?(cache_key)
         @logger.info("Returning cached machine: #{name} (#{provider})")
         return @machines[cache_key]

plugins/providers/virtualbox/action/check_box.rb

@@ -25,7 +25,7 @@ module VagrantPlugins
 
             # Reload the environment and set the VM to be the new loaded VM.
             env[:machine] = env[:machine].env.machine(
-              env[:machine].name, env[:machine].provider_name)
+              env[:machine].name, env[:machine].provider_name, true)
           end
 
           @app.call(env)

test/unit/vagrant/environment_test.rb

@@ -454,6 +454,30 @@ VF
       machine.config.ssh.port.should == 100
     end
 
+    it "should reload the cache if refresh is set" do
+      # Create a provider
+      foo_provider = register_provider("foo")
+
+      # Create the configuration
+      isolated_env = isolated_environment do |e|
+        e.vagrantfile(<<-VF)
+Vagrant.configure("2") do |config|
+  config.vm.box = "base"
+end
+VF
+
+        e.box2("base", :foo)
+      end
+
+      env = isolated_env.create_vagrant_env
+      vm1 = env.machine(:default, :foo)
+      vm2 = env.machine(:default, :foo, true)
+      vm3 = env.machine(:default, :foo)
+
+      vm1.should_not eql(vm2)
+      vm2.should eql(vm3)
+    end
+
     it "should raise an error if the VM is not found" do
       expect { instance.machine("i-definitely-dont-exist", :virtualbox) }.
         to raise_error(Vagrant::Errors::MachineNotFound)