Update build_query_vars_from_query_block to handle new taxQuery structure

[ntsekouras]

Trac ticket: https://core.trac.wordpress.org/ticket/64416

In GB we've updated the structure of Query Loop's taxQuery to also handle exclusion of terms in this PR (WordPress/gutenberg#73790).

The new structure is:

{
	query: {
		taxQuery: {
			include: {
				category: [1, 2, 3],
				post_tag: [10, 20]
			}
			exclude: {
				category: [5, 6],
				post_tag: [15]
			}
		}
	}
}

We need to update build_query_vars_from_query_block to handle this new taxQuery structure.

Testing instructions

Since this change should be handling Query Loop structure for 7.0 after the packages sync, we can test by:

1. Create two posts and post category.
2. Add the new post category to one of your posts.
3. In one post (doesn't matter which) insert a custom Query Loop (through inspector controls) and add a taxonomy:category filter with your created category.
4. In that post, switch to the code editor and add the below code for a Query Loop that includes the new taxQuery structure. Make sure to update the category id from the snippet, with the category id you've created. This refers to the "taxQuery":{"include":{"category":[3]}} part, where you should probably need to update the 3.

<!-- wp:query {"queryId":35,"query":{"perPage":2,"pages":0,"offset":0,"postType":"post","order":"desc","orderBy":"date","author":"","search":"","exclude":[],"sticky":"","inherit":false,"parents":[],"format":[],"taxQuery":{"include":{"category":[3]}}}} -->
<div class="wp-block-query"><!-- wp:post-template -->
<!-- wp:post-title /-->

<!-- wp:post-terms {"term":"category"} /-->

<!-- wp:post-terms {"term":"post_tag"} /-->

<!-- wp:post-date {"metadata":{"bindings":{"datetime":{"source":"core/post-data","args":{"field":"date"}}}}} /-->
<!-- /wp:post-template -->

<!-- wp:query-pagination -->
<!-- wp:query-pagination-previous /-->

<!-- wp:query-pagination-numbers /-->

<!-- wp:query-pagination-next /-->
<!-- /wp:query-pagination -->

<!-- wp:query-no-results -->
<!-- wp:paragraph {"placeholder":"Add text or blocks that will display when a query returns no results."} -->
<p></p>
<!-- /wp:paragraph -->
<!-- /wp:query-no-results --></div>
<!-- /wp:query -->

5. Save the post
6. Observe that in the editor the category filter should not work for the copied block (as the packages are not sync)
7. Visit front end and observe that the results are filtered properly based on the category for both blocks (old structure and the upcoming new structure).

---

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[github-actions]

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[github-actions]

The following accounts have interacted with this PR and/or linked issues. I will continue to update these lists as activity occurs. You can also manually ask me to refresh this list by adding the props-bot label.

Core Committers: Use this line as a base for the props when committing in SVN:

Props ntsekouras, westonruter, peterwilsoncc, mcsf.

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[westonruter]

Technically someone could have a taxonomy named include or exclude, no?

[ntsekouras]

Technically yes, but I'd consider it very hard to encounter.. This affects the REST API too and people can't use it properly since there is already the include to limit the result set to specific IDs and the respective exclude arg.

Not sure if we should consider updating register_taxonomy to have some reserved keys or update the REST API to somehow handle these cases, but maybe it's not worth it since it seems quite edge case to have taxonomies with these names? 🤔

[peterwilsoncc]

For the previous migration, we converted the old format to the new prior to constructing the query.

wordpress-develop/src/wp-includes/blocks.php

Lines 2697 to 2715 in edaed03

	// Migrate `categoryIds` and `tagIds` to `tax_query` for backwards compatibility.
	if ( ! empty( $block->context['query']['categoryIds'] ) || ! empty( $block->context['query']['tagIds'] ) ) {
	$tax_query_back_compat = array();
	if ( ! empty( $block->context['query']['categoryIds'] ) ) {
	$tax_query_back_compat[] = array(
	'taxonomy' => 'category',
	'terms' => array_filter( array_map( 'intval', $block->context['query']['categoryIds'] ) ),
	'include_children' => false,
	);
	}
	if ( ! empty( $block->context['query']['tagIds'] ) ) {
	$tax_query_back_compat[] = array(
	'taxonomy' => 'post_tag',
	'terms' => array_filter( array_map( 'intval', $block->context['query']['tagIds'] ) ),
	'include_children' => false,
	);
	}
	$query['tax_query'] = array_merge( $query['tax_query'], $tax_query_back_compat );
	}

I think migrating will make it easier for future developers following the code so I'd suggest doing so here.

As this is the third change to the taxQuery format, it might be worht doing it in a serate function wp_migrate_query_block_tax_query_or_something()

[ntsekouras]

For the previous migration, we converted the old format to the new prior to constructing the query.

We do the same with $tax_query here. Eventually they are added in $query['tax_query']. Did you mean something else?

I think migrating will make it easier for future developers following the code so I'd suggest doing so here.

As this is the third change to the taxQuery format, it might be worht doing it in a serate function wp_migrate_query_block_tax_query_or_something()

I thought about that while implementing this, but I felt it's better to keep it as is because:

1. The first migration had completely different props used, while this one changes the internal structure of query.taxQuery. With that, it feels more readable and easier to follow IMO because we check for if ( ! empty( $block->context['query']['taxQuery'] ) && is_array( $block->context['query']['taxQuery'] ) ) { once and then we have an if/else block for both structures
2. It's unfortunate how the dynamic blocks deprecations are handled (code lives forever in this file), but since I had to do this change, I wouldn't expect any more deprecations in the future for this attribute.

Said that, if you have a strong opinion on this I can update, but I don't feel it will make much difference personally.

[ntsekouras]

Do you think we can land as is based on my last comment or it's something more to address?

We need to land this soon for 7.0. Thanks!

[mcsf]

I didn't justify my approval, but just quickly:

• I reviewed it initially for Gutenberg
• The code has been in use there for a while
• LGTM here too, no surprises

[github-actions]

A commit was made that fixes the Trac ticket referenced in the description of this pull request.

SVN changeset: 61650
GitHub commit: 45e2aee

This PR will be closed, but please confirm the accuracy of this and reopen if there is more work to be done.