@Override
  public SpockExecutionContext prepare(SpockExecutionContext context) throws Exception {
    return ExceptionUtil.sneakyThrow(error);
  }
Always throws the error specified in {@link #ErrorSpecNode(UniqueId, RunnerConfiguration, SpecInfo, Throwable)},
escalating it up the call stack.
spock-core/src/main/java/org/spockframework/runtime/ErrorSpecNode.java