public static List<ConfigChangeAction> validateChanges(ChangeValidator validator, VespaModel model, DeployState deployState) {
        Execution execution = new Execution(model, deployState);
        validator.validate(execution);
        if ( ! execution.errors().isEmpty()) execution.throwIfFailed();
        return execution.actions();
    }
Runs validation and returns the resulting config chance actions, without checking whether they're currently allowed; or throws on illegalities.
config-model/src/test/java/com/yahoo/vespa/model/application/validation/ValidationTester.java