Rudimentary start domain action spec (#1167)

Add default domain start spec test and fix bug triggered by whitespace
mismatch in string comparison that would trigger unexpected domain
undefine and recreate.

spec/unit/action/start_domain_spec.rb

@@ -0,0 +1,49 @@
+require 'spec_helper'
+require 'support/sharedcontext'
+require 'support/libvirt_context'
+
+require 'vagrant-libvirt/errors'
+require 'vagrant-libvirt/action/start_domain'
+
+describe VagrantPlugins::ProviderLibvirt::Action::StartDomain do
+  subject { described_class.new(app, env) }
+
+  include_context 'unit'
+  include_context 'libvirt'
+
+  let(:libvirt_domain) { double('libvirt_domain') }
+  let(:libvirt_client) { double('libvirt_client') }
+  let(:servers) { double('servers') }
+
+  let(:domain_xml) { File.read(File.join(File.dirname(__FILE__), File.basename(__FILE__, '.rb'), test_file)) }
+
+  describe '#call' do
+    before do
+      allow_any_instance_of(VagrantPlugins::ProviderLibvirt::Driver)
+        .to receive(:connection).and_return(connection)
+      allow(connection).to receive(:client).and_return(libvirt_client)
+      allow(libvirt_client).to receive(:lookup_domain_by_uuid).and_return(libvirt_domain)
+
+      allow(connection).to receive(:servers).and_return(servers)
+      allow(servers).to receive(:get).and_return(domain)
+    end
+
+    context 'default config' do
+      let(:test_file) { 'default.xml' }
+
+      before do
+        allow(libvirt_domain).to receive(:xml_desc).and_return(domain_xml)
+
+        allow(libvirt_domain).to receive(:max_memory).and_return(512*1024)
+        allow(libvirt_domain).to receive(:num_vcpus).and_return(1)
+      end
+
+      it 'should execute correctly' do
+        expect(libvirt_domain).to receive(:autostart=)
+        expect(domain).to receive(:start)
+
+        expect(subject.call(env)).to be_nil
+      end
+    end
+  end
+end