BUGFIX: Adjust allowed workspaces list

[pKallert]

resolved: #4001

Review instructions
I adjusted the function for the base workspace options list so that if an excluded workspace is set, all of its child workspaces cannot be shown as well.
The query should check for each workspace if the excluded workspace is one of its base workspaces.
If the excluded workspace is one of its base workspaces, the workspace will not be shown in the options.

For testing: This change could influence the Edit-view and the New-view of the workspace module.

I am unsure if I should rename the variable $excludedWorkspace or if I should add a new variable $excludeChildWorkspaces to the method.

Checklist

• Code follows the PSR-2 coding style
• Tests have been created, run and adjusted as needed
• The PR is created against the lowest maintained branch
• Reviewer - PR Title is brief but complete and starts with FEATURE|TASK|BUGFIX
• Reviewer - The first section explains the change briefly for change-logs
• Reviewer - Breaking Changes are marked with !!! and have upgrade-instructions

[Sebobo]

Thx, looks good by reading

[grebaldi]

Hi @pKallert,

thx for fixing this :)

I was able to reproduce the issue and to verify that your fix works as expected 👍

I'm fine with merging this as-is, but I'd like to point out that as a follow up, this should be added as a constraint check to the Workspace model. I'm thinking of adding two new methods to the Workspace:

• isAncestorOf(Workspace $other): bool
• isAllowedToBecomeAncestorOf(Workspace $other): bool

And then let the existing setBaseWorkspace method throw an exception if a descendant is attempted to be set as a base workspace. The above methods then could also be used to filter the workspace list in the WorkspacesController (as per this PR).

This way, this condition would be properly captured at the domain level.

[markusguenther]

Thanks for the fix @pKallert 💙