ansible/test/integration/targets/lvg/tasks/test_grow_reduce.yml

- name: "Create volume group on first disk"
  lvg:
    vg: testvg
    pvs: "{{ loop_device1.stdout }}"

- name: "get lvm facts"
  setup:

- debug: var=ansible_lvm

- name: "Assert the testvg span only on first disk"
  assert:
    that:
      - ansible_lvm.pvs[loop_device1.stdout].vg == "testvg"
      - 'loop_device2.stdout not in ansible_lvm.pvs or
         ansible_lvm.pvs[loop_device2.stdout].vg == ""'

- name: "Extend to second disk AND reduce from the first disk"
  lvg:
    vg: testvg
    pvs: "{{ loop_device2.stdout }}"

- name: "get lvm facts"
  setup:

- debug: var=ansible_lvm

- name: "Assert the testvg span only on first disk"
  assert:
    that:
      - 'loop_device1.stdout not in ansible_lvm.pvs or
         ansible_lvm.pvs[loop_device1.stdout].vg == ""'
      - ansible_lvm.pvs[loop_device2.stdout].vg == "testvg"