ansible.utils/tests/integration/targets/update_fact/tasks/main.yaml

- name: Set a fact
  set_fact:
    a:
      b:
        c:
        - 1
        - 2

- name: Update the fact
  ansible.utils.update_fact:
    updates:
    - path: a.b.c.0
      value: 10
    - path: "a['b']['c'][1]"
      value: 20
  register: updated

- assert:
    that: "{{ updated.a == expected.a }}"
  vars:
    expected:
      a:
        b:
          c:
          - 10
          - 20

- name: Update the fact
  ansible.utils.update_fact:
    updates:
    - path: a
      value:
        x:
          y:
            z:
            - 100
            - True
  register: updated

- assert:
    that: "{{ updated.a == expected.a }}"
  vars:
    expected:
      a:
        x:
          y:
            z:
            - 100
            - True

- name: Update the fact
  ansible.utils.update_fact:
    updates:
    - path: "a.b.c[{{ index }}]"
      value: 20
  vars:
    index: "{{ a.b.c|ansible.utils.index_of('eq', 2) }}"
  register: updated

- assert:
    that: "{{ updated.a == expected.a }}"
  vars:
    expected:
      a:
        b:
          c:
          - 1
          - 20