Explore importing block templates and parts from shared directories

[iandunn]

If #1 is viable, then the next hurdle would be the ability for the child to import templates from the parent.

If it's not, then the collection of standalone themes will need a way to import templates from a shared library (a horizontal relationship, rather than hierarchical). Something like that will be critical for the maintainability as we create more themes for other parts of w.org.

Related WordPress/gutenberg#33959, WordPress/gutenberg#33957

[iandunn]

The theme template parts are included here:

https://github.com/WordPress/gutenberg/blob/4f5360e47c9874e52fd74a6b7693e90e107fa2d2/packages/block-library/src/template-part/index.php#L56

The only way I see to customize that would be to use the stylesheet_directory filter, check the stack trace, and if the called is render_block_core_template_part, then change the location.

We could also automate forking them from another repo, ala wporg-repo-tools/bin/update-configs, but that doesn't seem worth it.

So yeah, lets just do everything in the child for now, and then hopefully #13 will be unblocked by the time we go to build the 2nd theme 🤷🏻

If it's not, then maybe we can help push that forward in G before starting the 2nd repo.

[iandunn]

A couple other ideas:

• have a php file hook into the template rendering process just before fse does, load the html from an arbitrary location, and unhook fse loader? - seems fragile, probably not worth it
• have the .html file start a <?php block because it'll be processed by php anyway? this doesn't seem to work at first glance, but need to understand why before discounting it.
• create a "global footer" dynamic block, and include that - this seems possible today, and the most practical option. i'm going to explore that as part of Implement global header/footer design for News site #6 / #7

in the future, WordPress/gutenberg#32939 might make that workaround unnecessary. it also has some related issues linked to it

[iandunn]

WordPress/gutenberg#34354 made it so parent templates are inherited into child themes