Show Facet widgets on taxonomy archives

[burhandodhy]

Description of the Change

This PR adds the ability to show the Facet widgets on the taxonomy archives.

Closes #2808

Verification Process

• Add the Facet Widget.
• Go to a product category archive
• See the facets

Changelog Entry

Fixed: Show Facet widgets on taxonomy archives

Credits

Props @burhandodhy

[felipeelia]

@burhandodhy PHP linting found a problem in the code. Do you mind addressing it and then assigning the PR back to be for review? I think we might be being too simplistic in that new list of checks but I can check that later.

[burhandodhy]

@felipeelia liniting issues are fixed. For the check, I replicate the same behaviour which we have before.

[felipeelia]

For the check, I replicate the same behaviour which we have before.

Are you sure that

		if ( ! ( ( function_exists( 'is_product_category' ) && is_product_category() )
			|| $query->is_post_type_archive()
			|| $query->is_search()
			|| ( is_home() && empty( $query->get( 'page_id' ) ) ) )
		) {

behaves the same way

if ( $query->is_admin() || $query->is_singular() || $query->is_date() ) {

does?

Going to an author archive, just as an example, the code seems to have different behaviors.

Also, it is not needed to check if $query->is_admin() because we have a if ( is_admin() ) { a couple of lines above that already.

[burhandodhy]

@felipeelia thanks for pointing out the author archive page. I totally missed out that case. I updated the check.

[felipeelia]

@burhandodhy let's try to pass get_facetable_taxonomies() here (and possibly also get rid of is_tag() and is_category())

[burhandodhy]

@felipeelia I tried, but is_tax doesn't work for the built-in taxonomy page. We don't have any other option other than manually check every page.

Whether the query is for an existing custom taxonomy archive page. True for custom taxonomy archive pages, false for built-in taxonomies (category and tag archives). source