private Set<HostSpec> prepare(ApplicationId application, ProvisioningTester tester, ClusterSpec cluster, int nodeCount, int groups,
                                  boolean required, NodeResources nodeResources) {
        if (nodeCount == 0) return Set.of(); // this is a shady practice
        return new HashSet<>(tester.prepare(application, cluster, nodeCount, groups, required, nodeResources));
    }
Test always uses the zone default resources
node-repository/src/test/java/com/yahoo/vespa/hosted/provision/provisioning/ProvisioningTest.java