Navigation block: Use apply_block_hooks_to_content()

[ockham]

What?

In the Navigation block, use apply_block_hooks_to_content (introduced in WP 6.6), if available.

Why?

This is part of a centralization effort, i.e. to make apply_block_hooks_to_content the canonical entrypoint for applying the Block Hooks logic to a given piece of block markup. The same change has already been applied to the relevant call sites of Block Hooks logic in Core, see WordPress/wordpress-develop#7220.

This is particularly relevant for WordPress/wordpress-develop#7443, which will ensure that apply_block_hooks_to_content respects a hooked block's "multiple": false setting. In other words, the present PR is required to make sure that a hooked block isn't inserted more than once into a Navigation menu if it has "multiple": false set.

How?

By checking if apply_block_hooks_to_content exists, and if it does, by invoking it instead of the more indirect sequence of make_before_block_visitor/make_after_block_visitor, followed by traverse_and_serialize_block.

Testing Instructions

Verify that hooked blocks insertion into the Navigation menu works as before. For more detailed testing instructions, refer to #57754.

[github-actions]

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Co-authored-by: ockham <bernhard-reiter@git.wordpress.org>
Co-authored-by: ramonjd <ramonopoly@git.wordpress.org>
Co-authored-by: aaronrobertshaw <aaronrobertshaw@git.wordpress.org>

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[ramonjd]

I went through the test instructions in #57754

✅ The hooked_block_types PHP filter works as expected, including switching positions
✅ blockHooks in block.json also works as expected, including switching positions

The injected blocks only appear once

[aaronrobertshaw]

Thanks for the PR 👍

This tests as advertised for me:

✅ Login/Logout appears as inner block of core navigation block
✅ Block is only added once
✅ Block appears when editing header template part
✅ Custom positioning of block works and is persisted
✅ Removal of block works
✅ When using blockHooks in block.json, the same behaviour occurs

LGTM 🚢

[github-actions]

I just cherry-picked this PR to the wp/6.7 branch to get it included in the next release: e2f2dce

[ockham]

Thank you very much, @ramonjd and @aaronrobertshaw!

[ockham]

and @noisysocks 🙂