Set revision_default when publishing

I think this makes a lot of sense and it was an oversight that we didn't mark the revisions that are being published to Live as "was default revision". Added test coverage for this.

Since I only wrote the test coverage, I hope it's ok to RTBC the fix :)

Another random fail.

--- a/core/modules/workspaces/src/WorkspacePublisher.php
+++ b/core/modules/workspaces/src/WorkspacePublisher.php

@@ -106,6 +106,8 @@ public function publish() {
             // revisions.
             $entity->setSyncing(TRUE);
             $entity->isDefaultRevision(TRUE);
+            $revision_default_field = $entity->getEntityType()->getRevisionMetadataKey('revision_default');
+            $entity->{$revision_default_field}->value = TRUE;
 

$entity->isDefaultRevision() is already trying to do this so I don't think it's an oversight but rather something that ought to work, but in fact doesn't. To me this looks like working around ContentEntityBase not handling this situation. I can see working around it here, since fixing it in ContentEntityBase might not be straightforward, but think it at least needs a follow-up issue and @todo to try to address the issue directly in ContentEntityBase and an explanation of why we have to set revision default twice in two different ways.

Had a closer look at ContentEntityBase::doSave() and maybe it's not that bad to fix it there. Uploading just that patch to see whether it will cause a regression elsewhere.

Now with the test coverage added here.

Looks good to me as well! Back to RTBC because that was a random fail.

One more question - now that the fix is in ContentEntityBase, is there a generic revisions test we can squeeze an extra save and assertion into so that we're not relying on only workspaces for test coverage? Drupal\KernelTests\Core\Entity\EntityRevisionsTest seems like the right place.

Good point, here it is.

New test looks great. Back to RTBC for me.

This looks sensible and an easy edge case to have missed. The generic entity test looks nice.

Committed and pushed 29856d7482 to 10.0.x and 3f6a61e7eb to 9.5.x and 2c9e2db9c8 to 9.4.x and 9a3a6c1e5e to 9.3.x. Thanks!