What?

PR's goal is to optimize the Post Title block render time in the Editor by avoiding unnecessary requests in a particular case.

Why?

Post Title cannot be edited when it's a descendant of a query loop. However, in many cases, the OPTIONS request is made and then its result is ignored. On the pages with Query Loop and N Post Titles, it adds N number of OPTIONS requests that slow down loading the posts in the editor.

How?

This can be optimised, to make a call only when necessary.
Post title checks if it can be edited by useCanEditEntity usage. At the same time if isDescendentOfQueryLoop is true outcome of useCanEditEntity doesn't matter as it's check here and here.

Based on the above we could actually call useCanEditEntity only if isDescendentOfQueryLoop is false, however that's not allowed, as useCanEditEntity is a hook and cannot be called conditionally.

Using the fact that useCanEditEntity returns a falsy value (and skips making OPTIONS request) when there's no proper data we can conditionally provide "empty" data as arguments. That part probably could be improved to make it more bullet-proof, which I'm happy to get a feedback on.

One of the use cases for the above is the Products block from WooCommerce Blocks (variation of Query Loop block). WIth the 9 products there's an overhead of:

• on average ~0.7s of loading time on a Local setup
• on average ~1.5s of loading time on a remote setup

Testing Instructions

1. Go to Editor
2. Add a Query Loop block (choose option that includes Post Title)
3. Go to Dev Tools > Network tab
4. Look for /wp-json/wp/v2/posts/{POST ID} OPTIONS requests
5. Expected: There's no requests like that and title cannot be edited

1. Add a new post
2. Add a Post Title block
3. Go to Dev Tools > Network tab
4. Look for /wp-json/wp/v2/posts/{POST ID} OPTIONS requests
5. Expected: There's a request and title can be edited