core: Store the actual box data, not just the name

lib/vagrant/machine.rb

@@ -254,13 +254,21 @@ module Vagrant
         if index_uuid.nil?
           # Create the index entry and save it
           entry = MachineIndex::Entry.new
-          entry.extra_data["box"] = @config.vm.box
           entry.local_data_path = @env.local_data_path
           entry.name = @name.to_s
           entry.provider = @provider_name.to_s
           entry.state = "preparing"
           entry.vagrantfile_path = @env.root_path
           entry.vagrantfile_name = @env.vagrantfile_name
+
+          if @box
+            entry.extra_data["box"] = {
+              "name"     => @box.name,
+              "provider" => @box.provider.to_s,
+              "version"  => @box.version.to_s,
+            }
+          end
+
           entry = @env.machine_index.set(entry)
           @env.machine_index.release(entry)
 

test/unit/vagrant/machine_test.rb

@@ -403,7 +403,13 @@ describe Vagrant::Machine do
     end
 
     it "is set one when setting an ID" do
-      subject.config.vm.box = "FOO"
+      # Setup the box information
+      box = double("box")
+      box.stub(name: "foo")
+      box.stub(provider: :bar)
+      box.stub(version: "1.2.3")
+      subject.box = box
+
       subject.id = "foo"
 
       uuid = subject.index_uuid
@@ -412,12 +418,16 @@ describe Vagrant::Machine do
 
       # Test the entry itself
       entry = env.machine_index.get(uuid)
-      expect(entry.extra_data["box"]).to eq(subject.config.vm.box)
       expect(entry.name).to eq(subject.name)
       expect(entry.provider).to eq(subject.provider_name.to_s)
       expect(entry.state).to eq("preparing")
       expect(entry.vagrantfile_path).to eq(env.root_path)
       expect(entry.vagrantfile_name).to eq(env.vagrantfile_name)
+      expect(entry.extra_data["box"]).to eq({
+        "name"     => box.name,
+        "provider" => box.provider.to_s,
+        "version"  => box.version,
+      })
       env.machine_index.release(entry)
     end