ServerSpec unable to execute tests against remote windows ami

Question

I have a test machine that contains a serverspec test. This is a ubuntu machine and I want to run the test using WinRM against a windows machine.

when executing the test it immediately fails, it looks like it is trying to run the test locally and not against the remote host.

I have hardcoded the hostname in the spec_helper.rb for now but I will post the Rakefile for completness

Rakefile:

require 'rake'
require 'rspec/core/rake_task'

hosts = %w(

MyHostName )

task :spec => 'spec:all'
task :default => :spec
namespace :spec do
  task :all => hosts.map {|h| 'spec:' + h.split('.')[0] }
  hosts.each do |host|
    short_name = host.split('.')[0]
    role       = short_name.match(/[^0-9]+/)[0]

    desc "Run serverspec to #{host}"
    RSpec::Core::RakeTask.new(short_name) do |t|
      ENV['TARGET_HOST'] = host
      t.pattern = "spec/base/*_spec.rb"
    end
  end
end

Spec_helper.rb

require 'serverspec'
require 'winrm'

set :backend, :winrm

user = "Packer"
pass = "Drj33l1n9"
endpoint = "http://hostname:5985/wsman"


 opts = {
   user: user,
   password: pass,
   endpoint: endpoint,
   operation_timeout: 30,
 }

 winrm = WinRM::Connection.new ( opts)
 Specinfra.configuration.winrm = winrm

Sample_spec.rb

require 'spec_helper'
set :os, :family => 'windows'

describe file('c:/windows') do
  it { should be_directory }
end

describe file('c:/temp/testfile.txt') do
  it { should be_file }
end

describe service('Schedule') do
  it { should be_installed }
  it { should be_enabled }
  it { should be_running }
  it { should have_start_mode("Automatic") }
end

describe port(139) do
  it { should be_listening }
end

describe user('Administrator') do
  it { should exist }
  it { should belong_to_group('Administrators')}
end

this is the output of the failures

/usr/bin/ruby2.3 -I/var/lib/gems/2.3.0/gems/rspec-support-3.5.0/lib:/var/lib/gems/2.3.0/gems/rspec-core-3.5.4/lib /var/lib/gems/2.3.0/gems/rspec-core-3.5.4/exe/rspec --pattern spec/base/\*_spec.rb

File "c:/windows"
  should be directory (FAILED - 1)

File "c:/temp/testfile.txt"
  should be file (FAILED - 2)