Optimize term count update during post status transition

[pbearne]

The modification ensures that term counts are only updated when the post's status has truly changed. This reduces unnecessary operations, improving performance when there is no status change on a post.

Trac ticket: https://core.trac.wordpress.org/ticket/42522

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[peterwilsoncc]

This change makes sense.

My one concern is for custom taxonomies using the update_count_callback feature. Although I can not see how that would be a problem unless they're using the count column for a non-standard purpose.

Are you able to add some tests to ensure:

• Updating a post without changing the status doesn't attempt to update the count
  • I think checking the action edited_term_taxonomy does not fire will be suitable
  • Check that the count before and after is the same
• Updating a post to change the post status does update the count
  • increases by one when published
  • decreases by one when unpublished
• Modifying the terms without changing the post status triggers a recount/count is as expected
• anything else you think I've missed.

[peterwilsoncc]

Thanks Paul, I've added a couple of suggestions fo the tests to avoid repeating work unnecessarily

[peterwilsoncc]

I can't figure out why the unrelated tests have started failing.

For the most part they look to be arrays returning in a different order but I can't see how this change would affect that.