ansible/test/integration/targets/blocks/inherit_notify.yml

- hosts: localhost
  gather_facts: false
  tasks:
  - name: test notify inheritance in block
    notify: hello
    block:
    - debug: msg='trigger it'
      changed_when: true

  handlers:
    - name: hello
      set_fact: hello=world

  post_tasks:
    - name: ensure handler ran
      assert:
        that:
          - hello is defined
          - "hello == 'world'"