Plugins that have wp-blocks as a dependency break other plugins that use the filters in wp-blocks

[notnownikki]

Describe the bug

If you have a plugin that needs to register a filter function for blocks.registerBlockType and it gets loaded after a plugin that requires wp-blocks to be loaded (e.g. Jetpack) then the plugin will not register its filter function in time for it to be applied.

To Reproduce
Steps to reproduce the behavior:

1. Create a plugin that uses blocks.registerBlockType, make sure that its enqueue statements do not require wp-blocks as a dependency, (because it needs to load BEFORE that, so the filter can apply)
2. Install and activate a plugin which depends on wp-blocks (e.g. Jetpack)
3. See that the filter function in your plugin does not fire, because the plugin that depended on wp-blocks has made wp-blocks load too early for your plugin's filter function to be applied.

Expected behavior

Plugins should not be able to break other plugins by depending on wp-blocks. This may be affecting other filters too, but the ones in wp-blocks are the most obvious, because one of the most popular plugins for WP depends on wp-blocks, and so breaks all other plugins that use the filters.

[gziolo]

I was seeking some solution to this issue in the past: #10554. However, I don't plan to work further on this one since we are going to change the way how blocks can be registered after we agree on #13693. Depending on the final shape of blocks registration the solution proposed here might be completely different.

[notnownikki]

There's a PR at #14050 which is focused on providing an API for plugins to provide their own embed blocks, and hook into the URL -> Embed Block functionality. The code works, but I wrote a test to make sure that plugins using the API wouldn't break when Jetpack is installed, and that's how I found this bug - they do break.

Should I put that work on hold until the block registration work is complete?

[gziolo]

Should I put that work on hold until the block registration work is complete?

It might take some time to finish all improvements to the block registration. So I don't know what would be the best way to tackle it.

[notnownikki]

I think it had best wait, the current implementation relies on a filter, so if that's going to end up working after the registration work is complete then that's all good, if not then it would need quite a rework so I think it had best go on hold until the changes land and we can work with them in their final form. Thanks for the pointers :)

[Feniksss]

Hi @gziolo. Do you have any news about this problem? Also some strange observation - I had this problem with WP 5.4.2 only (for WP 5.3 all works correct)

[gziolo]

I have a proposal ready that should resolve this issue for blocks and filters that are registered before the editor screen is initialized. It should cover the majority of use cases. Related PR: #34299.