ansible/test/integration/targets/timezone/tasks/main.yml

- name: set timezone to Etc/UTC
  timezone:
    name: Etc/UTC

- name: set timezone to Australia/Brisbane
  timezone:
    name: Australia/Brisbane
  register: timezone_set

- name: ensure timezone changed
  assert:
    that:
      - timezone_set.changed
      - timezone_set.diff.after.name == 'Australia/Brisbane'
      - timezone_set.diff.before.name == 'Etc/UTC'