@Test
    void host_ttl_requires_cloud_account() throws Exception {
        var servicesXml = """
                          <services version='1.0'>
                            <container id='testcontainer' version='1.0'>
                              <nodes count='1'/>
                            </container>
                          </services>
                          """;

        var deploymentXml = """
                            <deployment version='1.0' empty-host-ttl='1d'>
                              <instance id='default'>
                                <prod>
                                  <region>us-east-1</region>
                                  <region empty-host-ttl='0m'>us-north-1</region>
                                  <region>us-west-1</region>
                                </prod>
                              </instance>
                            </deployment>
                            """;

        Cloud gcp = Cloud.builder().name(CloudName.GCP).account(CloudAccount.from("vespaz")).allowEnclave(true).build();
        CloudAccount account = CloudAccount.from("gcp:foobar");
        assertEquals(Duration.ofHours(24), requestedCapacityIn(account, gcp, "default", "us-east-1", servicesXml, deploymentXml).get(new ClusterSpec.Id("testcontainer")).clusterInfo().hostTTL());
        assertEquals(Duration.ZERO, requestedCapacityIn(account, gcp, "default", "us-north-1", servicesXml, deploymentXml).get(new ClusterSpec.Id("testcontainer")).clusterInfo().hostTTL());
        assertEquals(Duration.ZERO, requestedCapacityIn(CloudAccount.empty, gcp, "default", "us-west-1", servicesXml, deploymentXml).get(new Id("testcontainer")).clusterInfo().hostTTL());
    }
This implicitly creates one BCP group (which gives the same result as above).
config-model/src/test/java/com/yahoo/vespa/model/ClusterInfoTest.java