private void runIterationCleanups(SpockExecutionContext context) {
    for (Runnable cleanup : context.getCurrentIteration().getCleanups()) {
      try {
        cleanup.run();
      } catch (Throwable t) {
        ErrorInfo error = new ErrorInfo(CollectionUtil.getFirstElement(context.getSpec().getCleanupMethods()), t, ErrorContext.from(getSpecificationContext(context)));
        supervisor.error(context.getErrorInfoCollector(), error);
      }
    }
  }
Executes a single Spec. Notifies its supervisor about overall execution
progress and every invocation of Spec code.
Supervisor also determines the error strategy.

@author Peter Niederwieser
spock-core/src/main/java/org/spockframework/runtime/PlatformSpecRunner.java