core: Report the proper invalid state when waiting for the guest machine to be ready

CHANGELOG.md

@@ -7,6 +7,8 @@ IMPROVEMENTS:
 
 BUG FIXES:
 
+  - core: Report the proper invalid state when waiting for the guest machine
+    to be ready
   - core: `Guest#capability?` now works with strings as well
   - core: Fix NoMethodError in the new `Vagrant.has_plugin?` method [GH-2189]
   - hosts/arch: NFS exporting works properly, no exceptions. [GH-2161]

lib/vagrant/action/builtin/wait_for_communicator.rb

@@ -34,6 +34,8 @@ module Vagrant
             # Otherwise, periodically verify the VM isn't in a bad state.
             while true
               state = env[:machine].provider.state.id
+              # Used to report invalid states
+              Thread.current[:last_known_state] = state
               if !@states.include?(state)
                 Thread.current[:result] = false
                 break
@@ -51,7 +53,7 @@ module Vagrant
           if !states_thr[:result]
             raise Errors::VMBootBadState,
               valid: @states.join(", "),
-              invalid: env[:machine].provider.state.id
+              invalid: states_thr[:last_known_state]
           end
 
           # If it didn't boot, raise an error