(maint) Add Windows preparation specs

Adds spec tests for Windows-specific preparation, which primarily
involves retrieving the MSI when in a PE environment.

spec/classes/puppet_agent_osfamily_windows_spec.rb

@@ -0,0 +1,38 @@
+require 'spec_helper'
+
+describe 'puppet_agent', :unless => Puppet.version < "3.8.0" || Puppet.version >= "4.0.0" do
+  before(:each) do
+    # Need to mock the PE functions
+    Puppet::Parser::Functions.newfunction(:pe_build_version, :type => :rvalue) do |args|
+      "4.0.0"
+    end
+
+    Puppet::Parser::Functions.newfunction(:pe_compiling_server_aio_build, :type => :rvalue) do |args|
+      '1.2.5'
+    end
+  end
+
+  [['x64', 'x86_64'], ['x86', 'i386']].each do |arch, tag|
+    describe "supported Windows #{arch} environment" do
+      let(:appdata) { 'C:\ProgramData' }
+      let(:facts) {{
+        :is_pe          => true,
+        :osfamily       => 'windows',
+        :architecture   => arch,
+        :servername     => 'master.example.vm',
+        :clientcert     => 'foo.example.vm',
+        :puppet_confdir => "#{appdata}\\Puppetlabs\\puppet\\etc",
+        :mco_confdir    => "#{appdata}\\Puppetlabs\\mcollective\\etc",
+        :common_appdata => appdata,
+      }}
+
+      it { is_expected.to contain_file("#{appdata}\\Puppetlabs") }
+      it { is_expected.to contain_file("#{appdata}\\Puppetlabs\\packages") }
+      it {
+        is_expected.to contain_file("#{appdata}\\Puppetlabs\\packages/puppet-agent-#{arch}.msi").with(
+          'source' => "puppet:///pe_packages/4.0.0/windows-#{tag}/puppet-agent-#{arch}.msi"
+        )
+      }
+    end
+  end
+end