- name: valid template
  shell: ulimit -n
  vars:
    ansible_python_module_rlimit_nofile: "{{ 123 }}"
  register: result

- assert:
    that:
      - result.stdout | int == 123

- name: omit template
  shell: ulimit -n
  vars:
    ansible_python_module_rlimit_nofile: "{{ omit }}"
  register: result

- assert:
    that:
      - result.stdout | int == lookup('pipe', 'ulimit -n') | int

- name: undefined variable
  shell: ulimit -n
  vars:
    ansible_python_module_rlimit_nofile: "{{ undefined_variable }}"
  register: result
  ignore_errors: yes

- assert:
    that:
      - result is failed
      - result.msg is contains("undefined")