Correctly return nil if no valid adapters are present.

This should resolve #231

lib/vSphere/action/get_ssh_info.rb

@@ -24,6 +24,7 @@ def filter_guest_nic(vm, machine)
           interfaces = vm.guest.net.select { |g| g.deviceConfigId > 0 }
           ip_addresses = interfaces.map { |i| i.ipConfig.ipAddress.select { |a| a.state == 'preferred' } }.flatten
 
+          return nil if ip_addresses.empty?
           fail Errors::VSphereError.new, :'multiple_interface_with_real_nic_ip_set' if ip_addresses.size > 1
           ip_addresses.first.ipAddress
         end

spec/get_ssh_info_spec.rb

@@ -116,6 +116,15 @@
         expect(@env[:machine_ssh_info][:host]).to eq IP_ADDRESS
       end
 
+      context 'when the VM networking is uninitialized' do
+        before do
+          allow(@vm.guest).to receive(:net) {[]}
+        end
+        it 'should set the ssh info to nil if no valid adapters are present' do
+          call
+          expect(@env[:machine_ssh_info]).to eq nil
+        end
+      end
     end
   end
 end