This is extracted from #140967.
Previously, it was possible to sync a bundle/closure node based on what's linked.
However, it was not possible to detect if the syncing was possible or necessary
in the first place. Knowing this helps building UI features that inform the user
about outdated nodes.
Previously, the right sockets were already created on closure/bundle nodes when
link-drag-search is used. However, after initialization, there was no automatic
way to synchronize the sockets again after changes to one of the nodes. Instead
one had to copy the changes manually.
This patch adds a new operator that can automatically update the sockets on the
following nodes based on what is connected: Combine Bundle, Separate Bundle,
Closure (zone), Evaluate Closure.
The button is always visible in the side bar. In the future we may also want to
show it inside of the node when syncing is necessary. However, that's not done
in this patch. It's also a little bit tricky because detecting whether syncing
is necessary is not necessarily cheap (it requires traversing the tree including
going into nested node groups).
If no signature or conflicting signatures for the bundle or closure are found,
the operator does nothing. In this case, the user is currently responsible to
create/remove the sockets manually.
Pull Request: https://projects.blender.org/blender/blender/pulls/140449
