revoke celery chain eager mode

Question

I am using celery chain in Django project.

For chained tasks, I am using task_postrun signal to revoke all subsequent tasks similar to this.

@task_postrun.connect
def task_postrun_handler(
    signal, sender, task_id, task, retval, state, args, kwargs, **kwds
):
    # do other things first
    if retval != 1:
        task.request.chain[:] = []

So if the task's return value is not 1, then revoke all the subsequent tasks. It works fine.

However, in my test, I run the tasks in eager mode. It does enter the task_postrun_handler, but doesn't have array of chain ( the callbacks is None as well).

In this way, I am not able to terminate the task chains in my test. I tried both in celery 3.1.23 and celery 4.0.2

Thanks for any help.