Site Editor: Add theme taxonomy to templates and template parts

lib/edit-site-export.php

@@ -30,8 +30,13 @@ function gutenberg_edit_site_export() {
 		array(
 			'post_type'      => 'wp_template',
 			'post_status'    => array( 'publish', 'auto-draft' ),
-			'meta_key'       => 'theme',
-			'meta_value'     => $theme,
+			'tax_query'      => array(
+				array(
+					'taxonomy' => 'wp_theme',
+					'field'    => 'slug',
+					'terms'    => $theme,
+				),
+			),
 			'posts_per_page' => -1,
 			'no_found_rows'  => true,
 		)
@@ -49,8 +54,13 @@ function gutenberg_edit_site_export() {
 		array(
 			'post_type'      => 'wp_template_part',
 			'post_status'    => array( 'publish', 'auto-draft' ),
-			'meta_key'       => 'theme',
-			'meta_value'     => $theme,
+			'tax_query'      => array(
+				array(
+					'taxonomy' => 'wp_theme',
+					'field'    => 'slug',
+					'terms'    => $theme,
+				),
+			),
 			'posts_per_page' => -1,
 			'no_found_rows'  => true,
 		)

lib/template-loader.php

@@ -162,8 +162,13 @@ function gutenberg_resolve_template( $template_type, $template_hierarchy = array
 			'orderby'        => 'post_name__in',
 			'posts_per_page' => -1,
 			'no_found_rows'  => true,
-			'meta_key'       => 'theme',
-			'meta_value'     => wp_get_theme()->get_stylesheet(),
+			'tax_query'      => array(
+				array(
+					'taxonomy' => 'wp_theme',
+					'field'    => 'slug',
+					'terms'    => wp_get_theme()->get_stylesheet(),
+				),
+			),
 		)
 	);
 	$templates      = $template_query->get_posts();

lib/template-parts.php

@@ -55,40 +55,10 @@ function gutenberg_register_template_part_post_type() {
 		),
 	);
 
-	$meta_args = array(
-		'object_subtype' => 'wp_template_part',
-		'type'           => 'string',
-		'description'    => 'The theme that provided the template part, if any.',
-		'single'         => true,
-		'show_in_rest'   => true,
-	);
-
 	register_post_type( 'wp_template_part', $args );
-	register_meta( 'post', 'theme', $meta_args );
 }
 add_action( 'init', 'gutenberg_register_template_part_post_type' );
 
-/**
- * Automatically set the theme meta for template parts.
- *
- * @param array $post_id Template Part ID.
- * @param array $post    Template Part Post.
- * @param bool  $update  Is update.
- */
-function gutenberg_set_template_part_post_theme( $post_id, $post, $update ) {
-	if ( 'wp_template_part' !== $post->post_type || $update || 'trash' === $post->post_status ) {
-		return;
-	}
-
-	$theme = get_post_meta( $post_id, 'theme', true );
-
-	if ( ! $theme ) {
-		update_post_meta( $post_id, 'theme', wp_get_theme()->get_stylesheet() );
-	}
-}
-
-add_action( 'save_post', 'gutenberg_set_template_part_post_theme', 10, 3 );
-
 /**
  * Filters `wp_template_part` posts slug resolution to bypass deduplication logic as
  * template part slugs should be unique.
@@ -191,13 +161,14 @@ function filter_rest_wp_template_part_collection_params( $query_params ) {
  */
 function filter_rest_wp_template_part_query( $args, $request ) {
 	if ( $request['theme'] ) {
-		$meta_query   = isset( $args['meta_query'] ) ? $args['meta_query'] : array();
-		$meta_query[] = array(
-			'key'   => 'theme',
-			'value' => $request['theme'],
+		$tax_query   = isset( $args['tax_query'] ) ? $args['tax_query'] : array();
+		$tax_query[] = array(
+			'taxonomy' => 'wp_theme',
+			'field'    => 'slug',
+			'terms'    => $request['theme'],
 		);
 
-		$args['meta_query'] = $meta_query;
+		$args['tax_query'] = $tax_query;
 	}
 
 	return $args;

lib/templates-sync.php

@@ -27,8 +27,13 @@ function _gutenberg_create_auto_draft_for_template( $post_type, $slug, $theme, $
 			'post_type'      => $post_type,
 			'post_status'    => array( 'publish', 'auto-draft' ),
 			'title'          => $slug,
-			'meta_key'       => 'theme',
-			'meta_value'     => $theme,
+			'tax_query'      => array(
+				array(
+					'taxonomy' => 'wp_theme',
+					'field'    => 'slug',
+					'terms'    => $theme,
+				),
+			),
 			'posts_per_page' => 1,
 			'no_found_rows'  => true,
 		)
@@ -42,6 +47,7 @@ function _gutenberg_create_auto_draft_for_template( $post_type, $slug, $theme, $
 				'post_status'  => 'auto-draft',
 				'post_type'    => $post_type,
 				'post_name'    => $slug,
+				'tax_input'    => array( 'wp_theme' => array( $theme, '_wp_file_based' ) ),
 			)
 		);
 	} elseif ( 'auto-draft' === $post->post_status && $content !== $post->post_content ) {

lib/templates.php

@@ -75,39 +75,55 @@ function gutenberg_register_template_post_type() {
 		),
 	);
 
-	$meta_args = array(
-		'object_subtype' => 'wp_template',
-		'type'           => 'string',
-		'description'    => 'The theme that provided the template, if any.',
-		'single'         => true,
-		'show_in_rest'   => true,
-	);
-
 	register_post_type( 'wp_template', $args );
-	register_meta( 'post', 'theme', $meta_args );
 }
 add_action( 'init', 'gutenberg_register_template_post_type' );
 
+/**
+ * Registers block editor 'wp_theme' taxonomy.
+ */
+function gutenberg_register_wp_theme_taxonomy() {
+	if ( ! gutenberg_is_fse_theme() ) {
+		return;
+	}
+
+	register_taxonomy(
+		'wp_theme',
+		array( 'wp_template', 'wp_template_part' ),
+		array(
+			'public'            => false,
+			'hierarchical'      => false,
+			'labels'            => array(
+				'name'          => __( 'Themes', 'gutenberg' ),
+				'singular_name' => __( 'Theme', 'gutenberg' ),
+			),
+			'query_var'         => false,
+			'rewrite'           => false,
+			'show_ui'           => false,
+			'_builtin'          => true,
+			'show_in_nav_menus' => false,
+			'show_in_rest'      => true,
+		)
+	);
+}
+add_action( 'init', 'gutenberg_register_wp_theme_taxonomy' );
+
 /**
  * Automatically set the theme meta for templates.
  *
  * @param array $post_id Template ID.
  * @param array $post    Template Post.
  * @param bool  $update  Is update.
  */
-function gutenberg_set_template_post_theme( $post_id, $post, $update ) {
-	if ( 'wp_template' !== $post->post_type || $update || 'trash' === $post->post_status ) {
-		return;
-	}
-
-	$theme = get_post_meta( $post_id, 'theme', true );
-
-	if ( ! $theme ) {
-		update_post_meta( $post_id, 'theme', wp_get_theme()->get_stylesheet() );
+function gutenberg_set_template_and_template_part_post_theme( $post_id, $post, $update ) {
+	$themes = wp_get_post_terms( $post_id, 'wp_theme' );
+	if ( ! $themes ) {
+		wp_set_post_terms( $post_id, array( wp_get_theme()->get_stylesheet() ), 'wp_theme', true );
 	}
 }
 
-add_action( 'save_post', 'gutenberg_set_template_post_theme', 10, 3 );
+add_action( 'save_post_wp_template', 'gutenberg_set_template_and_template_part_post_theme', 10, 3 );
+add_action( 'save_post_wp_template_part', 'gutenberg_set_template_and_template_part_post_theme', 10, 3 );
 
 /**
  * Filters the capabilities of a user to conditionally grant them capabilities for managing 'wp_template' posts.
@@ -322,3 +338,41 @@ function filter_rest_wp_template_query( $args, $request ) {
 }
 add_filter( 'rest_wp_template_query', 'filter_rest_wp_template_query', 99, 2 );
 
+/**
+ * Filters the post data for a response.
+ *
+ * @param WP_REST_Response $response The response object.
+ * @return WP_REST_Response
+ */
+function filter_rest_prepare_add_wp_theme_slug_and_file_based( $response ) {
+	if ( isset( $response->data ) && is_array( $response->data ) && isset( $response->data['id'] ) ) {
+		$response->data['wp_theme_slug'] = false;
+
+		// Get the wp_theme terms.
+		$wp_themes = wp_get_post_terms( $response->data['id'], 'wp_theme' );
+
+		// If a theme is assigned, add it to the REST response.
+		if ( $wp_themes && is_array( $wp_themes ) ) {
+			$wp_theme_slugs = array_column( $wp_themes, 'slug' );
+
+			$file_based                   = in_array( '_wp_file_based', $wp_theme_slugs, true );
+			$response->data['file_based'] = $file_based;
+
+			$theme_slug = array_values(
+				array_filter(
+					$wp_theme_slugs,
+					function( $slug ) {
+						return '_wp_file_based' !== $slug;
+					}
+				)
+			);
+			if ( $theme_slug ) {
+				$response->data['wp_theme_slug'] = $theme_slug[0];
+			}
+		}
+	}
+
+	return $response;
+}
+add_filter( 'rest_prepare_wp_template', 'filter_rest_prepare_add_wp_theme_slug_and_file_based' );
+add_filter( 'rest_prepare_wp_template_part', 'filter_rest_prepare_add_wp_theme_slug_and_file_based' );

packages/block-library/src/template-part/edit/placeholder/index.js

@@ -29,14 +29,13 @@ export default function TemplatePartPlaceholder( {
 				title,
 				status: 'publish',
 				slug,
-				meta: { theme: '' },
 				content: serialize( innerBlocks ),
 			}
 		);
 		setAttributes( {
 			postId: templatePart.id,
 			slug: templatePart.slug,
-			theme: templatePart.meta.theme,
+			theme: templatePart.wp_theme_slug,
 		} );
 	}, [ setAttributes ] );
 

packages/block-library/src/template-part/edit/selection/template-part-previews.js

@@ -31,11 +31,7 @@ function TemplatePartItem( {
 	onClose,
 	composite,
 } ) {
-	const {
-		id,
-		slug,
-		meta: { theme },
-	} = templatePart;
+	const { id, slug, wp_theme_slug: theme } = templatePart;
 	// The 'raw' property is not defined for a brief period in the save cycle.
 	// The fallback prevents an error in the parse function while saving.
 	const content = templatePart.content.raw || '';
@@ -103,15 +99,15 @@ function TemplatePartsByTheme( {
 	composite,
 } ) {
 	const templatePartsByTheme = useMemo( () => {
-		return Object.values( groupBy( templateParts, 'meta.theme' ) );
+		return Object.values( groupBy( templateParts, 'wp_theme_slug' ) );
 	}, [ templateParts ] );
 	const currentShownTPs = useAsyncList( templateParts );
 
 	return templatePartsByTheme.map( ( templatePartList ) => (
 		<PanelGroup
-			key={ templatePartList[ 0 ].meta.theme }
+			key={ templatePartList[ 0 ].wp_theme_slug }
 			// Falsy theme implies custom template part.
-			title={ templatePartList[ 0 ].meta.theme || __( 'Custom' ) }
+			title={ templatePartList[ 0 ].wp_theme_slug || __( 'Custom' ) }
 		>
 			{ templatePartList.map( ( templatePart ) => {
 				return currentShownTPs.includes( templatePart ) ? (
@@ -142,7 +138,7 @@ function TemplatePartSearchResults( {
 		// Remove diacritics and convert to lowercase to normalize.
 		const normalizedFilterValue = deburr( filterValue ).toLowerCase();
 		const searchResults = templateParts.filter(
-			( { slug, meta: { theme } } ) =>
+			( { slug, wp_theme_slug: theme } ) =>
 				slug.toLowerCase().includes( normalizedFilterValue ) ||
 				// Since diacritics can be used in theme names, remove them for the comparison.
 				deburr( theme ).toLowerCase().includes( normalizedFilterValue )
@@ -166,10 +162,10 @@ function TemplatePartSearchResults( {
 			// Second prioritize index found in theme.
 			// Since diacritics can be used in theme names, remove them for the comparison.
 			return (
-				deburr( a.meta.theme )
+				deburr( a.wp_theme_slug )
 					.toLowerCase()
 					.indexOf( normalizedFilterValue ) -
-				deburr( b.meta.theme )
+				deburr( b.wp_theme_slug )
 					.toLowerCase()
 					.indexOf( normalizedFilterValue )
 			);
@@ -182,7 +178,7 @@ function TemplatePartSearchResults( {
 	return filteredTPs.map( ( templatePart ) => (
 		<PanelGroup
 			key={ templatePart.id }
-			title={ templatePart.meta.theme || __( 'Custom' ) }
+			title={ templatePart.wp_theme_slug || __( 'Custom' ) }
 		>
 			{ currentShownTPs.includes( templatePart ) ? (
 				<TemplatePartItem

packages/block-library/src/template-part/edit/use-template-part-post.js

@@ -33,19 +33,12 @@ export default function useTemplatePartPost( postId, slug, theme ) {
 						theme,
 					}
 				);
-				const foundPosts = posts?.filter(
-					( post ) =>
-						post.slug === cleanedSlug &&
-						post.meta &&
-						post.meta.theme === theme
-				);
+
 				// A published post might already exist if this template part was customized elsewhere
 				// or if it's part of a customized template.
 				const foundPost =
-					foundPosts?.find( ( post ) => post.status === 'publish' ) ||
-					foundPosts?.find(
-						( post ) => post.status === 'auto-draft'
-					);
+					posts?.find( ( post ) => post.status === 'publish' ) ||
+					posts?.find( ( post ) => post.status === 'auto-draft' );
 				return foundPost?.id;
 			}
 		},

packages/block-library/src/template-part/index.php

@@ -25,8 +25,13 @@ function render_block_core_template_part( $attributes ) {
 				'post_type'      => 'wp_template_part',
 				'post_status'    => 'publish',
 				'name'           => $attributes['slug'],
-				'meta_key'       => 'theme',
-				'meta_value'     => $attributes['theme'],
+				'tax_query'      => array(
+					array(
+						'taxonomy' => 'wp_theme',
+						'field'    => 'slug',
+						'terms'    => $attributes['theme'],
+					),
+				),
 				'posts_per_page' => 1,
 				'no_found_rows'  => true,
 			)

packages/e2e-test-utils/README.md

@@ -636,6 +636,7 @@ Navigates to the post listing screen and bulk-trashes any posts which exist.
 _Parameters_
 
 -   _postType_ `string`: String slug for type of post to trash.
+-   _postStatus_ `string`: String status of posts to trash.
 
 _Returns_
 

packages/e2e-test-utils/src/posts.js

@@ -14,14 +14,16 @@ import { visitAdminPage } from './visit-admin-page';
  * Navigates to the post listing screen and bulk-trashes any posts which exist.
  *
  * @param {string} postType - String slug for type of post to trash.
+ * @param {string} postStatus - String status of posts to trash.
  *
  * @return {Promise} Promise resolving once posts have been trashed.
  */
-export async function trashAllPosts( postType = 'post' ) {
+export async function trashAllPosts( postType = 'post', postStatus ) {
 	await switchUserToAdmin();
 	// Visit `/wp-admin/edit.php` so we can see a list of posts and delete them.
 	const query = addQueryArgs( '', {
 		post_type: postType,
+		post_status: postStatus,
 	} ).slice( 1 );
 	await visitAdminPage( 'edit.php', query );