@Test
    public void testThatConfigChangeActionsAreCollectedFromAllModels() {
        List<Host> hosts = createHosts(9, "6.1.0", "6.2.0");
        List<ServiceInfo> services = createServices(1);

        List<ModelFactory> modelFactories = List.of(
                new ConfigChangeActionsModelFactory(Version.fromString("6.1.0"),
                                                    new VespaRestartAction(ClusterSpec.Id.from("test"), "change", services)),
                new ConfigChangeActionsModelFactory(Version.fromString("6.2.0"),
                                                    new VespaRestartAction(ClusterSpec.Id.from("test"), "other change", services)));

        DeployTester tester = createTester(hosts, modelFactories, prodZone);
        tester.deployApp("src/test/apps/hosted/", "6.2.0");

        assertEquals(9, tester.getAllocatedHostsOf(tester.applicationId()).getHosts().size());
    }
Test that deploying an application works when there are no allocated hosts in the system
(the bootstrap a new zone case, so deploying the routing app since that is the first deployment
that will be done)
configserver/src/test/java/com/yahoo/vespa/config/server/deploy/HostedDeployTest.java