Conditional role inclusion+run_once may skip tasks unexpectedly

[amenonsen]

ISSUE TYPE

• Bug Report

COMPONENT NAME

core

ANSIBLE VERSION

devel

CONFIGURATION

N/A

OS / ENVIRONMENT

N/A

SUMMARY

If a role is included conditionally, then any run_once task in it may be skipped if the first host that is running the play doesn't meet the condition.

STEPS TO REPRODUCE

foo.yml

---
- hosts: all
  gather_facts: no
  roles:
    - role: p
      when: inventory_hostname == 'c'

roles/p/tasks/main.yml:

- command: cat /proc/uptime
  run_once: true

I did this:

ansible-playbook -v -i a,b,c,d, -e ansible_connection=local i.yml

EXPECTED RESULTS

I expected the task to be executed on 'c'.

ACTUAL RESULTS

PLAY [all] ************************************************************************************************************************************************************************************

TASK [p : command] ****************************************************************************************************************************************************************************
skipping: [a] => {"changed": false, "skip_reason": "Conditional check failed", "skipped": true}

PLAY RECAP ************************************************************************************************************************************************************************************
a                          : ok=0    changed=0    unreachable=0    failed=0   

[krzysztof-magosa]

Related to #13226

[bcoca]

closing as dupe of #13226, this is a consequence of run_once running on the first active host in the run, so the when condition evaluates relative to that host.