community.general/test/integration/targets/file_lock/test_filelock.yml

---
- hosts: lockhosts
  gather_facts: no
  vars:
    lockfile: ~/ansible_testing/lock.test
  tasks:
  - name: Remove lockfile
    file:
      path: '{{ lockfile }}'
      state: absent
    run_once: yes

  - name: Write inventory_hostname to lockfile concurrently
    lineinfile:
      path: '{{ lockfile }}'
      line: '{{ inventory_hostname }}'
      create: yes
      state: present

  - debug:
      msg: File {{ lockfile }} has {{ lines|length }} lines for {{ ansible_play_batch|length }} instances
    vars:
      lines: "{{ lookup('file', lockfile).split('\n') }}"
    run_once: yes

  - name: Assert we get the expected number of lines
    assert:
      that:
      - lines|length == ansible_play_batch|length
    vars:
      lines: "{{ lookup('file', lockfile).split('\n') }}"
    run_once: yes

  - name: Check lockfile for inventory_hostname entries
    lineinfile:
      path: '{{ lockfile }}'
      line: '{{ inventory_hostname }}'
      state: present
    register: check_lockfile

  - name: Assert locking results
    assert:
      that:
      - check_lockfile is not changed
      - check_lockfile is not failed