[JENKINS-56935] Multibranch pipeline orphaned item strategy can't be set to 0

[ericcitaire]

See JENKINS-56935.

Proposed changelog entries

• Fixes JENKINS-56935

Submitter checklist

• JIRA issue is well described
• Changelog entry appropriate for the audience affected by the change (users or developer, depending on the change).
  * Use the Internal: prefix if the change has no user-visible impact (API, test frameworks, etc.)
• Appropriate autotests or explanation to why this change has no tests

[ericcitaire]

Can I have feedback on this please ?

ping @fcojfernandez @bitwiseman @alecharp

[jtnord]

this would be incorrect as the code is setting the internal value to -1 when the value is empty. by allowing 0 the internal field would no longer be using -1 and the quick deletion would no longer work.

If the behaviour is unclear I would suggest a change to the inline help and documentation rather than code

[ericcitaire]

this would be incorrect as the code is setting the internal value to -1 when the value is empty. by allowing 0 the internal field would no longer be using -1 and the quick deletion would no longer work.

If the behaviour is unclear I would suggest a change to the inline help and documentation rather than code

Yes, the behaviour is unclear.
From what I observe, my understanding is that an empty value or -1 basically means ignore this criteria, while a 0 value means don't keep anything.

Also, this is just a matter of UX because the 0 value is actually accepted, despite the displayed error message.