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

- name: Test ANSIBLE_DUPLICATE_YAML_DICT_KEY=warn
  command: ansible-playbook {{ verbosity }} {{ role_path }}/playbook.yml
  environment:
    ANSIBLE_DUPLICATE_YAML_DICT_KEY: warn
  register: duplicate_warn

- assert:
    that:
      - '"found a duplicate dict key (foo)" in duplicate_warn.stderr'
      - duplicate_warn.rc == 0

- name: Test ANSIBLE_DUPLICATE_YAML_DICT_KEY=error
  command: ansible-playbook {{ verbosity }} {{ role_path }}/playbook.yml
  failed_when: duplicate_error.rc != 4
  environment:
    ANSIBLE_DUPLICATE_YAML_DICT_KEY: error
  register: duplicate_error

- assert:
    that:
      - '"found a duplicate dict key (foo)" in duplicate_error.stderr'
      - duplicate_error.rc == 4

- name: Test ANSIBLE_DUPLICATE_YAML_DICT_KEY=ignore
  command: ansible-playbook {{ verbosity }} {{ role_path }}/playbook.yml
  environment:
    ANSIBLE_DUPLICATE_YAML_DICT_KEY: ignore
  register: duplicate_ignore

- assert:
    that:
      - '"found a duplicate dict key (foo)" not in duplicate_ignore.stderr'
      - duplicate_ignore.rc == 0