@Test
    void singlenode_servicespec_is_used_with_hosts_xml() throws IOException, SAXException {
        String servicesXml = "<container id='default' version='1.0' />";
        String hostsXml = "<hosts>\n" +
                "    <host name=\"test1.yahoo.com\">\n" +
                "        <alias>node1</alias>\n" +
                "    </host>\n" +
                "</hosts>";
        ApplicationPackage applicationPackage = new MockApplicationPackage.Builder()
                .withHosts(hostsXml)
                .withServices(servicesXml)
                .build();
        VespaModel model = new VespaModel(applicationPackage);
        assertEquals(1, model.hostSystem().getHosts().size());
    }
Tests for "core functionality" of the container model, e.g. ports, or the 'components' and 'bundles' configs.

Before adding a new test to this class, check if the test fits into one of the other existing subclasses
of {@link ContainerModelBuilderTestBase}. If not, consider creating a new subclass.

@author gjoranv
config-model/src/test/java/com/yahoo/vespa/model/container/xml/ContainerModelBuilderTest.java