Changeset 52062

Timestamp:

11/08/2021 11:09:53 PM (5 years ago)

Author:

noisysocks

Message:

Editor: Add block theme infrastructure

Adds the required infrastructure to render block-based themes. This is sourced
from the Gutenberg plugin.

Fixes #54335.
Props bernhard-reiter, youknowriad, ntsekouras, hellofromtonya.

Location:

trunk

Files:

• src/wp-includes/block-template-utils.php (modified) (11 diffs)
• src/wp-includes/blocks.php (modified) (1 diff)
• src/wp-includes/blocks/index.php (modified) (1 diff)
• src/wp-includes/blocks/template-part (added)
• src/wp-includes/blocks/template-part.php (added)
• src/wp-includes/blocks/template-part/block.json (added)
• src/wp-includes/class-wp-block-template.php (modified) (1 diff)
• src/wp-includes/class-wp-theme-json.php (modified) (2 diffs)
• src/wp-includes/default-filters.php (modified) (1 diff)
• src/wp-includes/post.php (modified) (1 diff)
• src/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php (modified) (8 diffs)
• src/wp-includes/taxonomy.php (modified) (3 diffs)
• src/wp-includes/theme-templates.php (modified) (2 diffs)
• tests/phpunit/data/templates (added)
• tests/phpunit/data/templates/template.html (added)
• tests/phpunit/includes/functions.php (modified) (1 diff)
• tests/phpunit/tests/block-template-utils.php (modified) (6 diffs)
• tests/phpunit/tests/rest-api/rest-schema-setup.php (modified) (1 diff)
• tests/qunit/fixtures/wp-api-generated.js (modified) (3 diffs)
• tools/webpack/blocks.js (modified) (1 diff)

trunk/src/wp-includes/block-template-utils.php

@@ -1 +1 @@
 <?php
 /**
- * Utilities used to fetch and create templates.
+ * Utilities used to fetch and create templates and template parts.
  *
  * @package WordPress
@@ -7 +7 @@
  */
 
+// Define constants for supported wp_template_part_area taxonomy.
+if ( ! defined( 'WP_TEMPLATE_PART_AREA_HEADER' ) ) {
+        define( 'WP_TEMPLATE_PART_AREA_HEADER', 'header' );
+}
+if ( ! defined( 'WP_TEMPLATE_PART_AREA_FOOTER' ) ) {
+        define( 'WP_TEMPLATE_PART_AREA_FOOTER', 'footer' );
+}
+if ( ! defined( 'WP_TEMPLATE_PART_AREA_SIDEBAR' ) ) {
+        define( 'WP_TEMPLATE_PART_AREA_SIDEBAR', 'sidebar' );
+}
+if ( ! defined( 'WP_TEMPLATE_PART_AREA_UNCATEGORIZED' ) ) {
+        define( 'WP_TEMPLATE_PART_AREA_UNCATEGORIZED', 'uncategorized' );
+}
+
+/**
+ * Returns a filtered list of allowed area values for template parts.
+ *
+ * @since 5.9.0
+ *
+ * @return array The supported template part area values.
+ */
+function get_allowed_block_template_part_areas() {
+        $default_area_definitions = array(
+                array(
+                        'area'        => WP_TEMPLATE_PART_AREA_UNCATEGORIZED,
+                        'label'       => __( 'General' ),
+                        'description' => __(
+                                'General templates often perform a specific role like displaying post content, and are not tied to any particular area.'
+                        ),
+                        'icon'        => 'layout',
+                        'area_tag'    => 'div',
+                ),
+                array(
+                        'area'        => WP_TEMPLATE_PART_AREA_HEADER,
+                        'label'       => __( 'Header' ),
+                        'description' => __(
+                                'The Header template defines a page area that typically contains a title, logo, and main navigation.'
+                        ),
+                        'icon'        => 'header',
+                        'area_tag'    => 'header',
+                ),
+                array(
+                        'area'        => WP_TEMPLATE_PART_AREA_FOOTER,
+                        'label'       => __( 'Footer' ),
+                        'description' => __(
+                                'The Footer template defines a page area that typically contains site credits, social links, or any other combination of blocks.'
+                        ),
+                        'icon'        => 'footer',
+                        'area_tag'    => 'footer',
+                ),
+        );
+
+        /**
+         * Filters the list of allowed template part area values.
+         *
+         * @since 5.9.0
+         *
+         * @param array $default_areas An array of supported area objects.
+         */
+        return apply_filters( 'default_wp_template_part_areas', $default_area_definitions );
+}
+
+
+/**
+ * Returns a filtered list of default template types, containing their
+ * localized titles and descriptions.
+ *
+ * @since 5.9.0
+ *
+ * @return array The default template types.
+ */
+function get_default_block_template_types() {
+        $default_template_types = array(
+                'index'          => array(
+                        'title'       => _x( 'Index', 'Template name' ),
+                        'description' => __( 'The default template used when no other template is available. This is a required template in WordPress.' ),
+                ),
+                'home'           => array(
+                        'title'       => _x( 'Home', 'Template name' ),
+                        'description' => __( 'Template used for the main page that displays blog posts. This is the front page by default in WordPress. If a static front page is set, this is the template used for the page that contains the latest blog posts.' ),
+                ),
+                'front-page'     => array(
+                        'title'       => _x( 'Front Page', 'Template name' ),
+                        'description' => __( 'Template used to render the front page of the site, whether it displays blog posts or a static page. The front page template takes precedence over the "Home" template.' ),
+                ),
+                'singular'       => array(
+                        'title'       => _x( 'Singular', 'Template name' ),
+                        'description' => __( 'Template used for displaying single views of the content. This template is a fallback for the Single, Post, and Page templates, which take precedence when they exist.' ),
+                ),
+                'single'         => array(
+                        'title'       => _x( 'Single Post', 'Template name' ),
+                        'description' => __( 'Template used to display a single blog post.' ),
+                ),
+                'page'           => array(
+                        'title'       => _x( 'Page', 'Template name' ),
+                        'description' => __( 'Template used to display individual pages.' ),
+                ),
+                'archive'        => array(
+                        'title'       => _x( 'Archive', 'Template name' ),
+                        'description' => __( 'The archive template displays multiple entries at once. It is used as a fallback for the Category, Author, and Date templates, which take precedence when they are available.' ),
+                ),
+                'author'         => array(
+                        'title'       => _x( 'Author', 'Template name' ),
+                        'description' => __( 'Archive template used to display a list of posts from a single author.' ),
+                ),
+                'category'       => array(
+                        'title'       => _x( 'Category', 'Template name' ),
+                        'description' => __( 'Archive template used to display a list of posts from the same category.' ),
+                ),
+                'taxonomy'       => array(
+                        'title'       => _x( 'Taxonomy', 'Template name' ),
+                        'description' => __( 'Archive template used to display a list of posts from the same taxonomy.' ),
+                ),
+                'date'           => array(
+                        'title'       => _x( 'Date', 'Template name' ),
+                        'description' => __( 'Archive template used to display a list of posts from a specific date.' ),
+                ),
+                'tag'            => array(
+                        'title'       => _x( 'Tag', 'Template name' ),
+                        'description' => __( 'Archive template used to display a list of posts with a given tag.' ),
+                ),
+                'attachment'     => array(
+                        'title'       => __( 'Media' ),
+                        'description' => __( 'Template used to display individual media items or attachments.' ),
+                ),
+                'search'         => array(
+                        'title'       => _x( 'Search', 'Template name' ),
+                        'description' => __( 'Template used to display search results.' ),
+                ),
+                'privacy-policy' => array(
+                        'title'       => __( 'Privacy Policy' ),
+                        'description' => '',
+                ),
+                '404'            => array(
+                        'title'       => _x( '404', 'Template name' ),
+                        'description' => __( 'Template shown when no content is found.' ),
+                ),
+        );
+
+        /**
+         * Filters the list of template types.
+         *
+         * @since 5.9.0
+         *
+         * @param array $default_template_types An array of template types, formatted as [ slug => [ title, description ] ].
+         */
+        return apply_filters( 'default_template_types', $default_template_types );
+}
+
+/**
+ * Checks whether the input 'area' is a supported value.
+ * Returns the input if supported, otherwise returns the 'uncategorized' value.
+ *
+ * @access private
+ * @since 5.9.0
+ *
+ * @param string $type Template part area name.
+ *
+ * @return string Input if supported, else the uncategorized value.
+ */
+function _filter_block_template_part_area( $type ) {
+        $allowed_areas = array_map(
+                static function ( $item ) {
+                        return $item['area'];
+                },
+                get_allowed_block_template_part_areas()
+        );
+        if ( in_array( $type, $allowed_areas, true ) ) {
+                return $type;
+        }
+
+        $warning_message = sprintf(
+                /* translators: %1$s: Template area type, %2$s: the uncategorized template area value. */
+                __( '"%1$s" is not a supported wp_template_part area value and has been added as "%2$s".' ),
+                $type,
+                WP_TEMPLATE_PART_AREA_UNCATEGORIZED
+        );
+        trigger_error( $warning_message, E_USER_NOTICE );
+        return WP_TEMPLATE_PART_AREA_UNCATEGORIZED;
+}
+
+/**
+ * Finds all nested template part file paths in a theme's directory.
+ *
+ * @access private
+ * @since 5.9.0
+ *
+ * @param string $base_directory The theme's file path.
+ * @return array $path_list A list of paths to all template part files.
+ */
+function _get_block_templates_paths( $base_directory ) {
+        $path_list = array();
+        if ( file_exists( $base_directory ) ) {
+                $nested_files      = new RecursiveIteratorIterator( new RecursiveDirectoryIterator( $base_directory ) );
+                $nested_html_files = new RegexIterator( $nested_files, '/^.+\.html$/i', RecursiveRegexIterator::GET_MATCH );
+                foreach ( $nested_html_files as $path => $file ) {
+                        $path_list[] = $path;
+                }
+        }
+        return $path_list;
+}
+
+/**
+ * Retrieves the template file from the theme for a given slug.
+ *
+ * @access private
+ * @since 5.9.0
+ *
+ * @param string $template_type wp_template or wp_template_part.
+ * @param string $slug template slug.
+ *
+ * @return array|null Template.
+ */
+function _get_block_template_file( $template_type, $slug ) {
+        if ( 'wp_template' !== $template_type && 'wp_template_part' !== $template_type ) {
+                return null;
+        }
+
+        $template_base_paths = array(
+                'wp_template'      => 'block-templates',
+                'wp_template_part' => 'block-template-parts',
+        );
+        $themes              = array(
+                get_stylesheet() => get_stylesheet_directory(),
+                get_template()   => get_template_directory(),
+        );
+        foreach ( $themes as $theme_slug => $theme_dir ) {
+                $file_path = $theme_dir . '/' . $template_base_paths[ $template_type ] . '/' . $slug . '.html';
+                if ( file_exists( $file_path ) ) {
+                        $new_template_item = array(
+                                'slug'  => $slug,
+                                'path'  => $file_path,
+                                'theme' => $theme_slug,
+                                'type'  => $template_type,
+                        );
+
+                        if ( 'wp_template_part' === $template_type ) {
+                                return _add_block_template_part_area_info( $new_template_item );
+                        }
+
+                        if ( 'wp_template' === $template_type ) {
+                                return _add_block_template_info( $new_template_item );
+                        }
+
+                        return $new_template_item;
+                }
+        }
+
+        return null;
+}
+
+/**
+ * Retrieves the template files from  the theme.
+ *
+ * @access private
+ * @since 5.9.0
+ *
+ * @param string $template_type wp_template or wp_template_part.
+ *
+ * @return array Template.
+ */
+function _get_block_templates_files( $template_type ) {
+        if ( 'wp_template' !== $template_type && 'wp_template_part' !== $template_type ) {
+                return null;
+        }
+
+        $template_base_paths = array(
+                'wp_template'      => 'block-templates',
+                'wp_template_part' => 'block-template-parts',
+        );
+        $themes              = array(
+                get_stylesheet() => get_stylesheet_directory(),
+                get_template()   => get_template_directory(),
+        );
+
+        $template_files = array();
+        foreach ( $themes as $theme_slug => $theme_dir ) {
+                $theme_template_files = _get_block_templates_paths( $theme_dir . '/' . $template_base_paths[ $template_type ] );
+                foreach ( $theme_template_files as $template_file ) {
+                        $template_base_path = $template_base_paths[ $template_type ];
+                        $template_slug      = substr(
+                                $template_file,
+                                // Starting position of slug.
+                                strpos( $template_file, $template_base_path . DIRECTORY_SEPARATOR ) + 1 + strlen( $template_base_path ),
+                                // Subtract ending '.html'.
+                                -5
+                        );
+                        $new_template_item = array(
+                                'slug'  => $template_slug,
+                                'path'  => $template_file,
+                                'theme' => $theme_slug,
+                                'type'  => $template_type,
+                        );
+
+                        if ( 'wp_template_part' === $template_type ) {
+                                $template_files[] = _add_block_template_part_area_info( $new_template_item );
+                        }
+
+                        if ( 'wp_template' === $template_type ) {
+                                $template_files[] = _add_block_template_info( $new_template_item );
+                        }
+                }
+        }
+
+        return $template_files;
+}
+
+/**
+ * Attempts to add custom template information to the template item.
+ *
+ * @access private
+ * @since 5.9.0
+ *
+ * @param array $template_item Template to add information to (requires 'slug' field).
+ * @return array Template
+ */
+function _add_block_template_info( $template_item ) {
+        if ( ! WP_Theme_JSON_Resolver::theme_has_support() ) {
+                return $template_item;
+        }
+
+        $theme_data = WP_Theme_JSON_Resolver::get_theme_data()->get_custom_templates();
+        if ( isset( $theme_data[ $template_item['slug'] ] ) ) {
+                $template_item['title']     = $theme_data[ $template_item['slug'] ]['title'];
+                $template_item['postTypes'] = $theme_data[ $template_item['slug'] ]['postTypes'];
+        }
+
+        return $template_item;
+}
+
+/**
+ * Attempts to add the template part's area information to the input template.
+ *
+ * @access private
+ * @since 5.9.0
+ *
+ * @param array $template_info Template to add information to (requires 'type' and 'slug' fields).
+ *
+ * @return array Template.
+ */
+function _add_block_template_part_area_info( $template_info ) {
+        if ( WP_Theme_JSON_Resolver::theme_has_support() ) {
+                $theme_data = WP_Theme_JSON_Resolver::get_theme_data()->get_template_parts();
+        }
+
+        if ( isset( $theme_data[ $template_info['slug'] ]['area'] ) ) {
+                $template_info['title'] = $theme_data[ $template_info['slug'] ]['title'];
+                $template_info['area']  = _filter_block_template_part_area( $theme_data[ $template_info['slug'] ]['area'] );
+        } else {
+                $template_info['area'] = WP_TEMPLATE_PART_AREA_UNCATEGORIZED;
+        }
+
+        return $template_info;
+}
+
+/**
+ * Returns an array containing the references of
+ * the passed blocks and their inner blocks.
+ *
+ * @access private
+ * @since 5.9.0
+ *
+ * @param array $blocks array of blocks.
+ *
+ * @return array block references to the passed blocks and their inner blocks.
+ */
+function _flatten_blocks( &$blocks ) {
+        $all_blocks = array();
+        $queue      = array();
+        foreach ( $blocks as &$block ) {
+                $queue[] = &$block;
+        }
+
+        while ( count( $queue ) > 0 ) {
+                $block = &$queue[0];
+                array_shift( $queue );
+                $all_blocks[] = &$block;
+
+                if ( ! empty( $block['innerBlocks'] ) ) {
+                        foreach ( $block['innerBlocks'] as &$inner_block ) {
+                                $queue[] = &$inner_block;
+                        }
+                }
+        }
+
+        return $all_blocks;
+}
+
+/**
+ * Parses wp_template content and injects the current theme's
+ * stylesheet as a theme attribute into each wp_template_part
+ *
+ * @access private
+ * @since 5.9.0
+ *
+ * @param string $template_content serialized wp_template content.
+ *
+ * @return string Updated wp_template content.
+ */
+function _inject_theme_attribute_in_block_template_content( $template_content ) {
+        $has_updated_content = false;
+        $new_content         = '';
+        $template_blocks     = parse_blocks( $template_content );
+
+        $blocks = _flatten_blocks( $template_blocks );
+        foreach ( $blocks as &$block ) {
+                if (
+                        'core/template-part' === $block['blockName'] &&
+                        ! isset( $block['attrs']['theme'] )
+                ) {
+                        $block['attrs']['theme'] = wp_get_theme()->get_stylesheet();
+                        $has_updated_content     = true;
+                }
+        }
+
+        if ( $has_updated_content ) {
+                foreach ( $template_blocks as &$block ) {
+                        $new_content .= serialize_block( $block );
+                }
+
+                return $new_content;
+        }
+
+        return $template_content;
+}
+
+/**
+ * Build a unified template object based on a theme file.
+ *
+ * @access private
+ * @since 5.9.0
+ *
+ * @param array $template_file Theme file.
+ * @param array $template_type wp_template or wp_template_part.
+ *
+ * @return WP_Block_Template Template.
+ */
+function _build_block_template_result_from_file( $template_file, $template_type ) {
+        $default_template_types = get_default_block_template_types();
+        $template_content       = file_get_contents( $template_file['path'] );
+        $theme                  = wp_get_theme()->get_stylesheet();
+
+        $template                 = new WP_Block_Template();
+        $template->id             = $theme . '//' . $template_file['slug'];
+        $template->theme          = $theme;
+        $template->content        = _inject_theme_attribute_in_block_template_content( $template_content );
+        $template->slug           = $template_file['slug'];
+        $template->source         = 'theme';
+        $template->type           = $template_type;
+        $template->title          = ! empty( $template_file['title'] ) ? $template_file['title'] : $template_file['slug'];
+        $template->status         = 'publish';
+        $template->has_theme_file = true;
+        $template->is_custom      = true;
+
+        if ( 'wp_template' === $template_type && isset( $default_template_types[ $template_file['slug'] ] ) ) {
+                $template->description = $default_template_types[ $template_file['slug'] ]['description'];
+                $template->title       = $default_template_types[ $template_file['slug'] ]['title'];
+                $template->is_custom   = false;
+        }
+
+        if ( 'wp_template' === $template_type && isset( $template_file['postTypes'] ) ) {
+                $template->post_types = $template_file['postTypes'];
+        }
+
+        if ( 'wp_template_part' === $template_type && isset( $template_file['area'] ) ) {
+                $template->area = $template_file['area'];
+        }
+
+        return $template;
+}
+
 /**
  * Build a unified template object based a post Object.
  *
  * @access private
- * @since 5.8.0
+ * @since 5.9.0
  *
  * @param WP_Post $post Template post.
@@ -17 +488 @@
  * @return WP_Block_Template|WP_Error Template.
  */
-function _build_template_result_from_post( $post ) {
-        $terms = get_the_terms( $post, 'wp_theme' );
+function _build_block_template_result_from_post( $post ) {
+        $default_template_types = get_default_block_template_types();
+        $terms                  = get_the_terms( $post, 'wp_theme' );
 
         if ( is_wp_error( $terms ) ) {
@@ -28 +500 @@
         }
 
-        $theme = $terms[0]->name;
+        $theme          = $terms[0]->name;
+        $has_theme_file = wp_get_theme()->get_stylesheet() === $theme &&
+                null !== _get_block_template_file( $post->post_type, $post->post_name );
 
         $template                 = new WP_Block_Template();
@@ -41 +515 @@
         $template->title          = $post->post_title;
         $template->status         = $post->post_status;
-        $template->has_theme_file = false;
+        $template->has_theme_file = $has_theme_file;
+        $template->is_custom      = true;
+
+        if ( 'wp_template' === $post->post_type && isset( $default_template_types[ $template->slug ] ) ) {
+                $template->is_custom = false;
+        }
+
+        if ( 'wp_template_part' === $post->post_type ) {
+                $type_terms = get_the_terms( $post, 'wp_template_part_area' );
+                if ( ! is_wp_error( $type_terms ) && false !== $type_terms ) {
+                        $template->area = $type_terms[0]->name;
+                }
+        }
 
         return $template;
@@ -54 +540 @@
  *     Optional. Arguments to retrieve templates.
  *
- *     @type array  $slug__in List of slugs to include.
- *     @type int    $wp_id Post ID of customized template.
+ *     @type array  $slug__in  List of slugs to include.
+ *     @type int    $wp_id     Post ID of customized template.
+ *     @type string $area      A 'wp_template_part_area' taxonomy value to filter by (for wp_template_part template type only).
+ *     @type string $post_type Post type to get the templates for.
  * }
- * @param string $template_type Optional. The template type (post type). Default 'wp_template'.
- * @return WP_Block_Template[] Block template objects.
+ * @param array $template_type wp_template or wp_template_part.
+ *
+ * @return array Templates.
  */
 function get_block_templates( $query = array(), $template_type = 'wp_template' ) {
+        /**
+         * Filters the block templates array before the query takes place.
+         *
+         * Return a non-null value to bypass the WordPress queries.
+         *
+         * @since 5.9
+         *
+         * @param WP_Block_Template[]|null $block_templates Return an array of block templates to short-circuit the default query,
+         *                                                  or null to allow WP to run it's normal queries.
+         * @param array $query {
+         *     Optional. Arguments to retrieve templates.
+         *
+         *     @type array  $slug__in List of slugs to include.
+         *     @type int    $wp_id Post ID of customized template.
+         *     @type string $post_type Post type to get the templates for.
+         * }
+         * @param array $template_type wp_template or wp_template_part.
+         */
+        $templates = apply_filters( 'pre_get_block_templates', null, $query, $template_type );
+        if ( ! is_null( $templates ) ) {
+                return $templates;
+        }
+
+        $post_type     = isset( $query['post_type'] ) ? $query['post_type'] : '';
         $wp_query_args = array(
                 'post_status'    => array( 'auto-draft', 'draft', 'publish' ),
@@ -75 +588 @@
         );
 
+        if ( 'wp_template_part' === $template_type && isset( $query['area'] ) ) {
+                $wp_query_args['tax_query'][]           = array(
+                        'taxonomy' => 'wp_template_part_area',
+                        'field'    => 'name',
+                        'terms'    => $query['area'],
+                );
+                $wp_query_args['tax_query']['relation'] = 'AND';
+        }
+
         if ( isset( $query['slug__in'] ) ) {
                 $wp_query_args['post_name__in'] = $query['slug__in'];
         }
 
-        // This is only needed for the regular templates CPT listing and editor.
+        // This is only needed for the regular templates/template parts CPT listing and editor.
         if ( isset( $query['wp_id'] ) ) {
                 $wp_query_args['p'] = $query['wp_id'];
@@ -89 +611 @@
         $query_result   = array();
         foreach ( $template_query->posts as $post ) {
-                $template = _build_template_result_from_post( $post );
-
-                if ( ! is_wp_error( $template ) ) {
-                        $query_result[] = $template;
-                }
-        }
-
-        return $query_result;
+                $template = _build_block_template_result_from_post( $post );
+
+                if ( is_wp_error( $template ) ) {
+                        continue;
+                }
+
+                if ( $post_type && ! $template->is_custom ) {
+                        continue;
+                }
+
+                $query_result[] = $template;
+        }
+
+        if ( ! isset( $query['wp_id'] ) ) {
+                $template_files = _get_block_templates_files( $template_type );
+                foreach ( $template_files as $template_file ) {
+                        $template = _build_block_template_result_from_file( $template_file, $template_type );
+
+                        if ( $post_type && ! $template->is_custom ) {
+                                continue;
+                        }
+
+                        if ( $post_type &&
+                                isset( $template->post_types ) &&
+                                ! in_array( $post_type, $template->post_types, true )
+                        ) {
+                                continue;
+                        }
+
+                        $is_not_custom   = false === array_search(
+                                wp_get_theme()->get_stylesheet() . '//' . $template_file['slug'],
+                                array_column( $query_result, 'id' ),
+                                true
+                        );
+                        $fits_slug_query =
+                                ! isset( $query['slug__in'] ) || in_array( $template_file['slug'], $query['slug__in'], true );
+                        $fits_area_query =
+                                ! isset( $query['area'] ) || $template_file['area'] === $query['area'];
+                        $should_include  = $is_not_custom && $fits_slug_query && $fits_area_query;
+                        if ( $should_include ) {
+                                $query_result[] = $template;
+                        }
+                }
+        }
+
+        /**
+         * Filters the array of queried block templates array after they've been fetched.
+         *
+         * @since 5.9
+         *
+         * @param WP_Block_Template[] $query_result Array of found block templates.
+         * @param array $query {
+         *     Optional. Arguments to retrieve templates.
+         *
+         *     @type array  $slug__in List of slugs to include.
+         *     @type int    $wp_id Post ID of customized template.
+         * }
+         * @param array $template_type wp_template or wp_template_part.
+         */
+        return apply_filters( 'get_block_templates', $query_result, $query, $template_type );
 }
 
@@ -105 +679 @@
  *
  * @param string $id            Template unique identifier (example: theme_slug//template_slug).
- * @param string $template_type Optional. The template type (post type). Default 'wp_template'.
+ * @param array  $template_type Optional. Template type: `'wp_template'` or '`wp_template_part'`.
+ *                              Default `'wp_template'`.
+ *
  * @return WP_Block_Template|null Template.
  */
 function get_block_template( $id, $template_type = 'wp_template' ) {
+        /**
+         * Filters the block templates array before the query takes place.
+         *
+         * Return a non-null value to bypass the WordPress queries.
+         *
+         * @since 5.9.0
+         *
+         * @param WP_Block_Template|null $block_template Return block template object to short-circuit the default query,
+         *                                               or null to allow WP to run its normal queries.
+         * @param string $id                             Template unique identifier (example: theme_slug//template_slug).
+         * @param array  $template_type                  Template type: `'wp_template'` or '`wp_template_part'`.
+         */
+        $block_template = apply_filters( 'pre_get_block_template', null, $id, $template_type );
+        if ( ! is_null( $block_template ) ) {
+                return $block_template;
+        }
+
         $parts = explode( '//', $id, 2 );
         if ( count( $parts ) < 2 ) {
@@ -132 +725 @@
 
         if ( count( $posts ) > 0 ) {
-                $template = _build_template_result_from_post( $posts[0] );
+                $template = _build_block_template_result_from_post( $posts[0] );
 
                 if ( ! is_wp_error( $template ) ) {
@@ -139 +732 @@
         }
 
-        return null;
-}
+        $block_template = get_block_file_template( $id, $template_type );
+
+        /**
+         * Filters the array of queried block templates array after they've been fetched.
+         *
+         * @since 5.9
+         *
+         * @param WP_Block_Template $block_template The found block template.
+         * @param string            $id             Template unique identifier (example: theme_slug//template_slug).
+         * @param array             $template_type  Template type: `'wp_template'` or '`wp_template_part'`.
+         */
+        return apply_filters( 'get_block_template', $block_template, $id, $template_type );
+}
+
+/**
+ * Retrieves a single unified template object using its id.
+ *
+ * @since 5.9.0
+ *
+ * @param string $id            Template unique identifier (example: theme_slug//template_slug).
+ * @param array  $template_type Optional. Template type: `'wp_template'` or '`wp_template_part'`.
+ *                              Default `'wp_template'`.
+ */
+function get_block_file_template( $id, $template_type = 'wp_template' ) {
+        /**
+         * Filters the block templates array before the query takes place.
+         *
+         * Return a non-null value to bypass the WordPress queries.
+         *
+         *
+         * @since 5.9.0
+         *
+         * @param WP_Block_Template|null $block_template Return block template object to short-circuit the default query,
+         *                                               or null to allow WP to run its normal queries.
+         * @param string $id                             Template unique identifier (example: theme_slug//template_slug).
+         * @param array  $template_type                  Template type: `'wp_template'` or '`wp_template_part'`.
+         */
+        $block_template = apply_filters( 'pre_get_block_file_template', null, $id, $template_type );
+        if ( ! is_null( $block_template ) ) {
+                return $block_template;
+        }
+
+        $parts = explode( '//', $id, 2 );
+        if ( count( $parts ) < 2 ) {
+                /** This filter is documented at the end of this function */
+                return apply_filters( 'get_block_file_template', null, $id, $template_type );
+        }
+        list( $theme, $slug ) = $parts;
+
+        if ( wp_get_theme()->get_stylesheet() !== $theme ) {
+                /** This filter is documented at the end of this function */
+                return apply_filters( 'get_block_file_template', null, $id, $template_type );
+        }
+
+        $template_file = _get_block_template_file( $template_type, $slug );
+        if ( null === $template_file ) {
+                /** This filter is documented at the end of this function */
+                return apply_filters( 'get_block_file_template', null, $id, $template_type );
+        }
+
+        $block_template = _build_block_template_result_from_file( $template_file, $template_type );
+
+        /**
+         * Filters the array of queried block templates array after they've been fetched.
+         *
+         * @since 5.9.0
+         *
+         * @param WP_Block_Template $block_template The found block template.
+         * @param string            $id             Template unique identifier (example: theme_slug//template_slug).
+         * @param array             $template_type  Template type: `'wp_template'` or '`wp_template_part'`.
+         */
+        return apply_filters( 'get_block_file_template', $block_template, $id, $template_type );
+}
+
+/**
+ * Print a template-part.
+ *
+ * @since 5.9.0
+ *
+ * @param string $part The template-part to print. Use "header" or "footer".
+ */
+function block_template_part( $part ) {
+        $template_part = get_block_template( get_stylesheet() . '//' . $part, 'wp_template_part' );
+        if ( ! $template_part || empty( $template_part->content ) ) {
+                return;
+        }
+        echo do_blocks( $template_part->content );
+}
+
+/**
+ * Print the header template-part.
+ *
+ * @since 5.9.0
+ */
+function block_header_area() {
+        block_template_part( 'header' );
+}
+
+/**
+ * Print the footer template-part.
+ *
+ * @since 5.9.0
+ */
+function block_footer_area() {
+        block_template_part( 'footer' );
+}

trunk/src/wp-includes/blocks.php

@@ -1155 +1155 @@
  * It's used in QueryPaginationNext and QueryPaginationPrevious blocks.
  *
+ * @since 5.9.0
+ *
  * @param WP_Block $block   Block instance.
  * @param boolean  $is_next Flag for hanlding `next/previous` blocks.

trunk/src/wp-includes/blocks/index.php

@@ -38 +38 @@
 require ABSPATH . WPINC . '/blocks/social-link.php';
 require ABSPATH . WPINC . '/blocks/tag-cloud.php';
+require ABSPATH . WPINC . '/blocks/template-part.php';
 
 /**

trunk/src/wp-includes/class-wp-block-template.php

@@ -101 +101 @@
          */
         public $has_theme_file;
+
+        /**
+         * Whether a template is a custom template.
+         *
+         * @since 5.9.0
+         *
+         * @var boolean
+         */
+        public $is_custom = true;
 }

trunk/src/wp-includes/class-wp-theme-json.php

@@ -602 +602 @@
         public function get_custom_templates() {
                 $custom_templates = array();
-                if ( ! isset( $this->theme_json['customTemplates'] ) ) {
+                if ( ! isset( $this->theme_json['customTemplates'] ) || ! is_array( $this->theme_json['customTemplates'] ) ) {
                         return $custom_templates;
                 }
@@ -626 +626 @@
         public function get_template_parts() {
                 $template_parts = array();
-                if ( ! isset( $this->theme_json['templateParts'] ) ) {
+                if ( ! isset( $this->theme_json['templateParts'] ) || ! is_array( $this->theme_json['templateParts'] ) ) {
                         return $template_parts;
                 }

trunk/src/wp-includes/default-filters.php

@@ -665 +665 @@
 add_filter( 'render_block_context', '_block_template_render_without_post_block_context' );
 add_filter( 'pre_wp_unique_post_slug', 'wp_filter_wp_template_unique_post_slug', 10, 5 );
+add_action( 'save_post_wp_template_part', 'wp_set_unique_slug_on_create_template_part' );
 add_action( 'wp_footer', 'the_block_template_skip_link' );
 add_action( 'setup_theme', 'wp_enable_block_templates' );

trunk/src/wp-includes/post.php

@@ -356 +356 @@
                         ),
                         'map_meta_cap'          => true,
+                        'supports'              => array(
+                                'title',
+                                'slug',
+                                'excerpt',
+                                'editor',
+                                'revisions',
+                        ),
+                )
+        );
+
+        register_post_type(
+                'wp_template_part',
+                array(
+                        'labels'                => array(
+                                'name'                  => __( 'Template Parts' ),
+                                'singular_name'         => __( 'Template Part' ),
+                                'add_new'               => _x( 'Add New', 'Template Part' ),
+                                'add_new_item'          => __( 'Add New Template Part' ),
+                                'new_item'              => __( 'New Template Part' ),
+                                'edit_item'             => __( 'Edit Template Part' ),
+                                'view_item'             => __( 'View Template Part' ),
+                                'all_items'             => __( 'All Template Parts' ),
+                                'search_items'          => __( 'Search Template Parts' ),
+                                'parent_item_colon'     => __( 'Parent Template Part:' ),
+                                'not_found'             => __( 'No template parts found.' ),
+                                'not_found_in_trash'    => __( 'No template parts found in Trash.' ),
+                                'archives'              => __( 'Template part archives' ),
+                                'insert_into_item'      => __( 'Insert into template part' ),
+                                'uploaded_to_this_item' => __( 'Uploaded to this template part' ),
+                                'filter_items_list'     => __( 'Filter template parts list' ),
+                                'items_list_navigation' => __( 'Template parts list navigation' ),
+                                'items_list'            => __( 'Template parts list' ),
+                        ),
+                        'description'           => __( 'Template parts to include in your templates.' ),
+                        'public'                => false,
+                        '_builtin'              => true, /* internal use only. don't use this when registering your own post type. */
+                        'has_archive'           => false,
+                        'show_ui'               => false,
+                        'show_in_menu'          => false,
+                        'show_in_rest'          => true,
+                        'rewrite'               => false,
+                        'rest_base'             => 'template-parts',
+                        'rest_controller_class' => 'WP_REST_Templates_Controller',
+                        'map_meta_cap'          => true,
+                        'capabilities'          => array(
+                                'create_posts'           => 'edit_theme_options',
+                                'delete_posts'           => 'edit_theme_options',
+                                'delete_others_posts'    => 'edit_theme_options',
+                                'delete_private_posts'   => 'edit_theme_options',
+                                'delete_published_posts' => 'edit_theme_options',
+                                'edit_posts'             => 'edit_theme_options',
+                                'edit_others_posts'      => 'edit_theme_options',
+                                'edit_private_posts'     => 'edit_theme_options',
+                                'edit_published_posts'   => 'edit_theme_options',
+                                'publish_posts'          => 'edit_theme_options',
+                                'read'                   => 'edit_theme_options',
+                                'read_private_posts'     => 'edit_theme_options',
+                        ),
                         'supports'              => array(
                                 'title',

trunk/src/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php

@@ -157 +157 @@
                         $query['area'] = $request['area'];
                 }
+                if ( isset( $request['post_type'] ) ) {
+                        $query['post_type'] = $request['post_type'];
+                }
 
                 $templates = array();
@@ -188 +191 @@
          */
         public function get_item( $request ) {
-                $template = get_block_template( $request['id'], $this->post_type );
+                if ( isset( $request['source'] ) && 'theme' === $request['source'] ) {
+                        $template = get_block_file_template( $request['id'], $this->post_type );
+                } else {
+                        $template = get_block_template( $request['id'], $this->post_type );
+                }
 
                 if ( ! $template ) {
@@ -221 +228 @@
                 if ( ! $template ) {
                         return new WP_Error( 'rest_template_not_found', __( 'No templates exist with that id.' ), array( 'status' => 404 ) );
+                }
+
+                if ( isset( $request['source'] ) && 'theme' === $request['source'] ) {
+                        wp_delete_post( $template->wp_id, true );
+                        return $this->prepare_item_for_response( get_block_file_template( $request['id'], $this->post_type ), $request );
                 }
 
@@ -396 +408 @@
                 }
 
+                if ( 'wp_template_part' === $this->post_type ) {
+                        if ( isset( $request['area'] ) ) {
+                                $changes->tax_input['wp_template_part_area'] = _filter_block_template_part_area( $request['area'] );
+                        } elseif ( null !== $template && 'custom' !== $template->source && $template->area ) {
+                                $changes->tax_input['wp_template_part_area'] = _filter_block_template_part_area( $template->area );
+                        } elseif ( ! $template->area ) {
+                                $changes->tax_input['wp_template_part_area'] = WP_TEMPLATE_PART_AREA_UNCATEGORIZED;
+                        }
+                }
+
                 return $changes;
         }
@@ -503 +525 @@
          *
          * @since 5.8.0
+         * @since 5.9.0 Added `'area'` and `'post_type'`.
          *
          * @return array Collection parameters.
@@ -508 +531 @@
         public function get_collection_params() {
                 return array(
-                        'context' => $this->get_context_param(),
-                        'wp_id'   => array(
+                        'context'   => $this->get_context_param(),
+                        'wp_id'     => array(
                                 'description' => __( 'Limit to the specified post id.' ),
                                 'type'        => 'integer',
                         ),
+                        'area'      => array(
+                                'description' => __( 'Limit to the specified template part area.' ),
+                                'type'        => 'string',
+                        ),
+                        'post_type' => array(
+                                'description' => __( 'Post type to get the templates for.' ),
+                                'type'        => 'string',
+                        ),
                 );
         }
@@ -520 +551 @@
          *
          * @since 5.8.0
+         * @since 5.9.0 Added `'area'`.
          *
          * @return array Item schema data.
@@ -597 +629 @@
                 );
 
+                if ( 'wp_template_part' === $this->post_type ) {
+                        $schema['properties']['area'] = array(
+                                'description' => __( 'Where the template part is intended for use (header, footer, etc.)' ),
+                                'type'        => 'string',
+                                'context'     => array( 'embed', 'view', 'edit' ),
+                        );
+                }
+
                 $this->schema = $schema;
 

trunk/src/wp-includes/taxonomy.php

@@ -19 +19 @@
  *
  * @since 2.8.0
+ * @since 5.9.0 Added `'wp_template_part_area'` taxonomy.
  *
  * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
@@ -176 +177 @@
         register_taxonomy(
                 'wp_theme',
-                array( 'wp_template', 'wp_global_styles' ),
+                array( 'wp_template', 'wp_template_part', 'wp_global_styles' ),
                 array(
                         'public'            => false,
@@ -183 +184 @@
                                 'name'          => __( 'Themes' ),
                                 'singular_name' => __( 'Theme' ),
+                        ),
+                        'query_var'         => false,
+                        'rewrite'           => false,
+                        'show_ui'           => false,
+                        '_builtin'          => true,
+                        'show_in_nav_menus' => false,
+                        'show_in_rest'      => false,
+                )
+        );
+
+        register_taxonomy(
+                'wp_template_part_area',
+                array( 'wp_template_part' ),
+                array(
+                        'public'            => false,
+                        'hierarchical'      => false,
+                        'labels'            => array(
+                                'name'          => __( 'Template Part Areas' ),
+                                'singular_name' => __( 'Template Part Area' ),
                         ),
                         'query_var'         => false,

trunk/src/wp-includes/theme-templates.php

@@ -1 +1 @@
 <?php
+
+/**
+ * Sets a custom slug when creating auto-draft template parts.
+ *
+ * This is only needed for auto-drafts created by the regular WP editor.
+ * If this page is to be removed, this won't be necessary.
+ *
+ * @since 5.9.0
+ *
+ */
+function wp_set_unique_slug_on_create_template_part( $post_id ) {
+        $post = get_post( $post_id );
+        if ( 'auto-draft' !== $post->post_status ) {
+                return;
+        }
+
+        if ( ! $post->post_name ) {
+                wp_update_post(
+                        array(
+                                'ID'        => $post_id,
+                                'post_name' => 'custom_slug_' . uniqid(),
+                        )
+                );
+        }
+
+        $terms = get_the_terms( $post_id, 'wp_theme' );
+        if ( ! is_array( $terms ) || ! count( $terms ) ) {
+                wp_set_post_terms( $post_id, wp_get_theme()->get_stylesheet(), 'wp_theme' );
+        }
+}
 
 /**
@@ -15 +45 @@
  */
 function wp_filter_wp_template_unique_post_slug( $override_slug, $slug, $post_ID, $post_status, $post_type ) {
-        if ( 'wp_template' !== $post_type ) {
+        if ( 'wp_template' !== $post_type && 'wp_template_part' !== $post_type ) {
                 return $override_slug;
         }

trunk/tests/phpunit/includes/functions.php

@@ -338 +338 @@
         remove_action( 'init', 'register_core_block_types_from_metadata' );
         remove_action( 'init', 'register_block_core_legacy_widget' );
+        remove_action( 'init', 'register_block_core_template_part' );
 }
 tests_add_filter( 'init', '_unhook_block_registration', 1000 );

trunk/tests/phpunit/tests/block-template-utils.php

@@ -7 +7 @@
 
 /**
- * Tests for the Block Template Loader abstraction layer.
+ * Tests for the Block Templates abstraction layer.
  */
 class Block_Template_Utils_Test extends WP_UnitTestCase {
         private static $post;
+        private static $template_part_post;
 
         public static function wpSetUpBeforeClass() {
+                // We may need a block theme.
+                // switch_theme( 'tt1-blocks' );
+
+                // Set up a template post corresponding to a different theme.
+                // We do this to ensure resolution and slug creation works as expected,
+                // even with another post of that same name present for another theme.
+                $args       = array(
+                        'post_type'    => 'wp_template',
+                        'post_name'    => 'my_template',
+                        'post_title'   => 'My Template',
+                        'post_content' => 'Content',
+                        'post_excerpt' => 'Description of my template',
+                        'tax_input'    => array(
+                                'wp_theme' => array(
+                                        'this-theme-should-not-resolve',
+                                ),
+                        ),
+                );
+                self::$post = self::factory()->post->create_and_get( $args );
+                wp_set_post_terms( self::$post->ID, 'this-theme-should-not-resolve', 'wp_theme' );
+
                 // Set up template post.
                 $args       = array(
@@ -28 +50 @@
                 self::$post = self::factory()->post->create_and_get( $args );
                 wp_set_post_terms( self::$post->ID, get_stylesheet(), 'wp_theme' );
+
+                // Set up template part post.
+                $template_part_args       = array(
+                        'post_type'    => 'wp_template_part',
+                        'post_name'    => 'my_template_part',
+                        'post_title'   => 'My Template Part',
+                        'post_content' => 'Content',
+                        'post_excerpt' => 'Description of my template part',
+                        'tax_input'    => array(
+                                'wp_theme'              => array(
+                                        get_stylesheet(),
+                                ),
+                                'wp_template_part_area' => array(
+                                        WP_TEMPLATE_PART_AREA_HEADER,
+                                ),
+                        ),
+                );
+                self::$template_part_post = self::factory()->post->create_and_get( $template_part_args );
+                wp_set_post_terms( self::$template_part_post->ID, WP_TEMPLATE_PART_AREA_HEADER, 'wp_template_part_area' );
+                wp_set_post_terms( self::$template_part_post->ID, get_stylesheet(), 'wp_theme' );
         }
 
@@ -35 +77 @@
 
         public function test_build_template_result_from_post() {
-                $template = _build_template_result_from_post(
+                $template = _build_block_template_result_from_post(
                         self::$post,
                         'wp_template'
@@ -41 +83 @@
 
                 $this->assertNotWPError( $template );
-                $this->assertSame( get_stylesheet() . '//my_template', $template->id );
-                $this->assertSame( get_stylesheet(), $template->theme );
-                $this->assertSame( 'my_template', $template->slug );
-                $this->assertSame( 'publish', $template->status );
-                $this->assertSame( 'custom', $template->source );
-                $this->assertSame( 'My Template', $template->title );
-                $this->assertSame( 'Description of my template', $template->description );
-                $this->assertSame( 'wp_template', $template->type );
+                $this->assertEquals( get_stylesheet() . '//my_template', $template->id );
+                $this->assertEquals( get_stylesheet(), $template->theme );
+                $this->assertEquals( 'my_template', $template->slug );
+                $this->assertEquals( 'publish', $template->status );
+                $this->assertEquals( 'custom', $template->source );
+                $this->assertEquals( 'My Template', $template->title );
+                $this->assertEquals( 'Description of my template', $template->description );
+                $this->assertEquals( 'wp_template', $template->type );
+
+                // Test template parts.
+                $template_part = _build_block_template_result_from_post(
+                        self::$template_part_post,
+                        'wp_template_part'
+                );
+                $this->assertNotWPError( $template_part );
+                $this->assertEquals( get_stylesheet() . '//my_template_part', $template_part->id );
+                $this->assertEquals( get_stylesheet(), $template_part->theme );
+                $this->assertEquals( 'my_template_part', $template_part->slug );
+                $this->assertEquals( 'publish', $template_part->status );
+                $this->assertEquals( 'custom', $template_part->source );
+                $this->assertEquals( 'My Template Part', $template_part->title );
+                $this->assertEquals( 'Description of my template part', $template_part->description );
+                $this->assertEquals( 'wp_template_part', $template_part->type );
+                $this->assertEquals( WP_TEMPLATE_PART_AREA_HEADER, $template_part->area );
+        }
+
+        function test_build_block_template_result_from_file() {
+                $template = _build_block_template_result_from_file(
+                        array(
+                                'slug' => 'single',
+                                'path' => __DIR__ . '/../data/templates/template.html',
+                        ),
+                        'wp_template'
+                );
+
+                $this->assertEquals( get_stylesheet() . '//single', $template->id );
+                $this->assertEquals( get_stylesheet(), $template->theme );
+                $this->assertEquals( 'single', $template->slug );
+                $this->assertEquals( 'publish', $template->status );
+                $this->assertEquals( 'theme', $template->source );
+                $this->assertEquals( 'Single Post', $template->title );
+                $this->assertEquals( 'Template used to display a single blog post.', $template->description );
+                $this->assertEquals( 'wp_template', $template->type );
+
+                // Test template parts.
+                $template_part = _build_block_template_result_from_file(
+                        array(
+                                'slug' => 'header',
+                                'path' => __DIR__ . '/../data/templates/template.html',
+                                'area' => WP_TEMPLATE_PART_AREA_HEADER,
+                        ),
+                        'wp_template_part'
+                );
+                $this->assertEquals( get_stylesheet() . '//header', $template_part->id );
+                $this->assertEquals( get_stylesheet(), $template_part->theme );
+                $this->assertEquals( 'header', $template_part->slug );
+                $this->assertEquals( 'publish', $template_part->status );
+                $this->assertEquals( 'theme', $template_part->source );
+                $this->assertEquals( 'header', $template_part->title );
+                $this->assertEquals( '', $template_part->description );
+                $this->assertEquals( 'wp_template_part', $template_part->type );
+                $this->assertEquals( WP_TEMPLATE_PART_AREA_HEADER, $template_part->area );
+        }
+
+        function test_inject_theme_attribute_in_block_template_content() {
+                $theme                           = get_stylesheet();
+                $content_without_theme_attribute = '<!-- wp:template-part {"slug":"header","align":"full", "tagName":"header","className":"site-header"} /-->';
+                $template_content                = _inject_theme_attribute_in_block_template_content(
+                        $content_without_theme_attribute,
+                        $theme
+                );
+                $expected                        = sprintf(
+                        '<!-- wp:template-part {"slug":"header","align":"full","tagName":"header","className":"site-header","theme":"%s"} /-->',
+                        get_stylesheet()
+                );
+                $this->assertEquals( $expected, $template_content );
+
+                $content_without_theme_attribute_nested = '<!-- wp:group --><!-- wp:template-part {"slug":"header","align":"full", "tagName":"header","className":"site-header"} /--><!-- /wp:group -->';
+                $template_content                       = _inject_theme_attribute_in_block_template_content(
+                        $content_without_theme_attribute_nested,
+                        $theme
+                );
+                $expected                               = sprintf(
+                        '<!-- wp:group --><!-- wp:template-part {"slug":"header","align":"full","tagName":"header","className":"site-header","theme":"%s"} /--><!-- /wp:group -->',
+                        get_stylesheet()
+                );
+                $this->assertEquals( $expected, $template_content );
+
+                // Does not inject theme when there is an existing theme attribute.
+                $content_with_existing_theme_attribute = '<!-- wp:template-part {"slug":"header","theme":"fake-theme","align":"full", "tagName":"header","className":"site-header"} /-->';
+                $template_content                      = _inject_theme_attribute_in_block_template_content(
+                        $content_with_existing_theme_attribute,
+                        $theme
+                );
+                $this->assertEquals( $content_with_existing_theme_attribute, $template_content );
+
+                // Does not inject theme when there is no template part.
+                $content_with_no_template_part = '<!-- wp:post-content /-->';
+                $template_content              = _inject_theme_attribute_in_block_template_content(
+                        $content_with_no_template_part,
+                        $theme
+                );
+                $this->assertEquals( $content_with_no_template_part, $template_content );
+        }
+
+        /**
+         * Should retrieve the template from the theme files.
+         */
+        function test_get_block_template_from_file() {
+                $this->markTestIncomplete();
+                // Requires switching to a block theme.
+                /* $id       = get_stylesheet() . '//' . 'index';
+                $template = get_block_template( $id, 'wp_template' );
+                $this->assertEquals( $id, $template->id );
+                $this->assertEquals( get_stylesheet(), $template->theme );
+                $this->assertEquals( 'index', $template->slug );
+                $this->assertEquals( 'publish', $template->status );
+                $this->assertEquals( 'theme', $template->source );
+                $this->assertEquals( 'wp_template', $template->type );
+
+                // Test template parts.
+                $id       = get_stylesheet() . '//' . 'header';
+                $template = get_block_template( $id, 'wp_template_part' );
+                $this->assertEquals( $id, $template->id );
+                $this->assertEquals( get_stylesheet(), $template->theme );
+                $this->assertEquals( 'header', $template->slug );
+                $this->assertEquals( 'publish', $template->status );
+                $this->assertEquals( 'theme', $template->source );
+                $this->assertEquals( 'wp_template_part', $template->type );
+                $this->assertEquals( WP_TEMPLATE_PART_AREA_HEADER, $template->area );
+                */
         }
 
@@ -57 +222 @@
                 $id       = get_stylesheet() . '//' . 'my_template';
                 $template = get_block_template( $id, 'wp_template' );
-                $this->assertSame( $id, $template->id );
-                $this->assertSame( get_stylesheet(), $template->theme );
-                $this->assertSame( 'my_template', $template->slug );
-                $this->assertSame( 'publish', $template->status );
-                $this->assertSame( 'custom', $template->source );
-                $this->assertSame( 'wp_template', $template->type );
+                $this->assertEquals( $id, $template->id );
+                $this->assertEquals( get_stylesheet(), $template->theme );
+                $this->assertEquals( 'my_template', $template->slug );
+                $this->assertEquals( 'publish', $template->status );
+                $this->assertEquals( 'custom', $template->source );
+                $this->assertEquals( 'wp_template', $template->type );
+
+                // Test template parts.
+                $id       = get_stylesheet() . '//' . 'my_template_part';
+                $template = get_block_template( $id, 'wp_template_part' );
+                $this->assertEquals( $id, $template->id );
+                $this->assertEquals( get_stylesheet(), $template->theme );
+                $this->assertEquals( 'my_template_part', $template->slug );
+                $this->assertEquals( 'publish', $template->status );
+                $this->assertEquals( 'custom', $template->source );
+                $this->assertEquals( 'wp_template_part', $template->type );
+                $this->assertEquals( WP_TEMPLATE_PART_AREA_HEADER, $template->area );
         }
 
         /**
-         * Should retrieve block templates.
+         * Should retrieve block templates (file and CPT)
          */
         public function test_get_block_templates() {
@@ -85 +261 @@
                 $this->assertContains( get_stylesheet() . '//' . 'my_template', $template_ids );
 
+                // The result might change in a block theme.
+                // $this->assertContains( get_stylesheet() . '//' . 'index', $template_ids );
+
                 // Filter by slug.
                 $templates    = get_block_templates( array( 'slug__in' => array( 'my_template' ) ), 'wp_template' );
                 $template_ids = get_template_ids( $templates );
-                $this->assertSame( array( get_stylesheet() . '//' . 'my_template' ), $template_ids );
+                $this->assertEquals( array( get_stylesheet() . '//' . 'my_template' ), $template_ids );
 
                 // Filter by CPT ID.
                 $templates    = get_block_templates( array( 'wp_id' => self::$post->ID ), 'wp_template' );
                 $template_ids = get_template_ids( $templates );
-                $this->assertSame( array( get_stylesheet() . '//' . 'my_template' ), $template_ids );
+                $this->assertEquals( array( get_stylesheet() . '//' . 'my_template' ), $template_ids );
+
+                // Filter template part by area.
+                // Requires a block theme.
+                /*$templates    = get_block_templates( array( 'area' => WP_TEMPLATE_PART_AREA_HEADER ), 'wp_template_part' );
+                $template_ids = get_template_ids( $templates );
+                $this->assertEquals(
+                        array(
+                                get_stylesheet() . '//' . 'my_template_part',
+                                get_stylesheet() . '//' . 'header',
+                        ),
+                        $template_ids
+                );
+                */
+        }
+
+        /**
+         * Should flatten nested blocks
+         */
+        function test_flatten_blocks() {
+                $content_template_part_inside_group = '<!-- wp:group --><!-- wp:template-part {"slug":"header"} /--><!-- /wp:group -->';
+                $blocks                             = parse_blocks( $content_template_part_inside_group );
+                $actual                             = _flatten_blocks( $blocks );
+                $expected                           = array( $blocks[0], $blocks[0]['innerBlocks'][0] );
+                $this->assertEquals( $expected, $actual );
+
+                $content_template_part_inside_group_inside_group = '<!-- wp:group --><!-- wp:group --><!-- wp:template-part {"slug":"header"} /--><!-- /wp:group --><!-- /wp:group -->';
+                $blocks   = parse_blocks( $content_template_part_inside_group_inside_group );
+                $actual   = _flatten_blocks( $blocks );
+                $expected = array( $blocks[0], $blocks[0]['innerBlocks'][0], $blocks[0]['innerBlocks'][0]['innerBlocks'][0] );
+                $this->assertEquals( $expected, $actual );
+
+                $content_without_inner_blocks = '<!-- wp:group /-->';
+                $blocks                       = parse_blocks( $content_without_inner_blocks );
+                $actual                       = _flatten_blocks( $blocks );
+                $expected                     = array( $blocks[0] );
+                $this->assertEquals( $expected, $actual );
         }
 }

trunk/tests/phpunit/tests/rest-api/rest-schema-setup.php

@@ -133 +133 @@
                         '/wp/v2/block-types/(?P<namespace>[a-zA-Z0-9_-]+)/(?P<name>[a-zA-Z0-9_-]+)',
                         '/wp/v2/settings',
+                        '/wp/v2/template-parts',
+                        '/wp/v2/template-parts/(?P<id>[\/\w-]+)',
+                        '/wp/v2/template-parts/(?P<id>[\d]+)/autosaves',
+                        '/wp/v2/template-parts/(?P<parent>[\d]+)/autosaves/(?P<id>[\d]+)',
+                        '/wp/v2/template-parts/(?P<parent>[\d]+)/revisions',
+                        '/wp/v2/template-parts/(?P<parent>[\d]+)/revisions/(?P<id>[\d]+)',
                         '/wp/v2/templates',
                         '/wp/v2/templates/(?P<id>[\/\w-]+)',

trunk/tests/qunit/fixtures/wp-api-generated.js

@@ -4165 +4165 @@
                             "type": "integer",
                             "required": false
+                        },
+                        "area": {
+                            "description": "Limit to the specified template part area.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "post_type": {
+                            "description": "Post type to get the templates for.",
+                            "type": "string",
+                            "required": false
                         }
                     }
@@ -4551 +4561 @@
         },
         "/wp/v2/templates/(?P<parent>[\\d]+)/autosaves/(?P<id>[\\d]+)": {
+            "namespace": "wp/v2",
+            "methods": [
+                "GET"
+            ],
+            "endpoints": [
+                {
+                    "methods": [
+                        "GET"
+                    ],
+                    "args": {
+                        "parent": {
+                            "description": "The ID for the parent of the autosave.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "id": {
+                            "description": "The ID for the autosave.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "context": {
+                            "description": "Scope under which the request is made; determines fields present in response.",
+                            "type": "string",
+                            "enum": [
+                                "view",
+                                "embed",
+                                "edit"
+                            ],
+                            "default": "view",
+                            "required": false
+                        }
+                    }
+                }
+            ]
+        },
+        "/wp/v2/template-parts": {
+            "namespace": "wp/v2",
+            "methods": [
+                "GET",
+                "POST"
+            ],
+            "endpoints": [
+                {
+                    "methods": [
+                        "GET"
+                    ],
+                    "args": {
+                        "context": {
+                            "description": "Scope under which the request is made; determines fields present in response.",
+                            "type": "string",
+                            "enum": [
+                                "view",
+                                "embed",
+                                "edit"
+                            ],
+                            "required": false
+                        },
+                        "wp_id": {
+                            "description": "Limit to the specified post id.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "area": {
+                            "description": "Limit to the specified template part area.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "post_type": {
+                            "description": "Post type to get the templates for.",
+                            "type": "string",
+                            "required": false
+                        }
+                    }
+                },
+                {
+                    "methods": [
+                        "POST"
+                    ],
+                    "args": {
+                        "slug": {
+                            "description": "Unique slug identifying the template.",
+                            "type": "string",
+                            "minLength": 1,
+                            "pattern": "[a-zA-Z_\\-]+",
+                            "required": true
+                        },
+                        "theme": {
+                            "description": "Theme identifier for the template.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "content": {
+                            "default": "",
+                            "description": "Content of template.",
+                            "type": [
+                                "object",
+                                "string"
+                            ],
+                            "required": false
+                        },
+                        "title": {
+                            "default": "",
+                            "description": "Title of template.",
+                            "type": [
+                                "object",
+                                "string"
+                            ],
+                            "required": false
+                        },
+                        "description": {
+                            "default": "",
+                            "description": "Description of template.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "status": {
+                            "default": "publish",
+                            "description": "Status of template.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "area": {
+                            "description": "Where the template part is intended for use (header, footer, etc.)",
+                            "type": "string",
+                            "required": false
+                        }
+                    }
+                }
+            ],
+            "_links": {
+                "self": [
+                    {
+                        "href": "http://example.org/index.php?rest_route=/wp/v2/template-parts"
+                    }
+                ]
+            }
+        },
+        "/wp/v2/template-parts/(?P<id>[\\/\\w-]+)": {
+            "namespace": "wp/v2",
+            "methods": [
+                "GET",
+                "POST",
+                "PUT",
+                "PATCH",
+                "DELETE"
+            ],
+            "endpoints": [
+                {
+                    "methods": [
+                        "GET"
+                    ],
+                    "args": {
+                        "id": {
+                            "description": "The id of a template",
+                            "type": "string",
+                            "required": false
+                        }
+                    }
+                },
+                {
+                    "methods": [
+                        "POST",
+                        "PUT",
+                        "PATCH"
+                    ],
+                    "args": {
+                        "slug": {
+                            "description": "Unique slug identifying the template.",
+                            "type": "string",
+                            "minLength": 1,
+                            "pattern": "[a-zA-Z_\\-]+",
+                            "required": false
+                        },
+                        "theme": {
+                            "description": "Theme identifier for the template.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "content": {
+                            "description": "Content of template.",
+                            "type": [
+                                "object",
+                                "string"
+                            ],
+                            "required": false
+                        },
+                        "title": {
+                            "description": "Title of template.",
+                            "type": [
+                                "object",
+                                "string"
+                            ],
+                            "required": false
+                        },
+                        "description": {
+                            "description": "Description of template.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "status": {
+                            "description": "Status of template.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "area": {
+                            "description": "Where the template part is intended for use (header, footer, etc.)",
+                            "type": "string",
+                            "required": false
+                        }
+                    }
+                },
+                {
+                    "methods": [
+                        "DELETE"
+                    ],
+                    "args": {
+                        "force": {
+                            "type": "boolean",
+                            "default": false,
+                            "description": "Whether to bypass Trash and force deletion.",
+                            "required": false
+                        }
+                    }
+                }
+            ]
+        },
+        "/wp/v2/template-parts/(?P<parent>[\\d]+)/revisions": {
+            "namespace": "wp/v2",
+            "methods": [
+                "GET"
+            ],
+            "endpoints": [
+                {
+                    "methods": [
+                        "GET"
+                    ],
+                    "args": {
+                        "parent": {
+                            "description": "The ID for the parent of the revision.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "context": {
+                            "description": "Scope under which the request is made; determines fields present in response.",
+                            "type": "string",
+                            "enum": [
+                                "view",
+                                "embed",
+                                "edit"
+                            ],
+                            "default": "view",
+                            "required": false
+                        },
+                        "page": {
+                            "description": "Current page of the collection.",
+                            "type": "integer",
+                            "default": 1,
+                            "minimum": 1,
+                            "required": false
+                        },
+                        "per_page": {
+                            "description": "Maximum number of items to be returned in result set.",
+                            "type": "integer",
+                            "minimum": 1,
+                            "maximum": 100,
+                            "required": false
+                        },
+                        "search": {
+                            "description": "Limit results to those matching a string.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "exclude": {
+                            "description": "Ensure result set excludes specific IDs.",
+                            "type": "array",
+                            "items": {
+                                "type": "integer"
+                            },
+                            "default": [],
+                            "required": false
+                        },
+                        "include": {
+                            "description": "Limit result set to specific IDs.",
+                            "type": "array",
+                            "items": {
+                                "type": "integer"
+                            },
+                            "default": [],
+                            "required": false
+                        },
+                        "offset": {
+                            "description": "Offset the result set by a specific number of items.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "order": {
+                            "description": "Order sort attribute ascending or descending.",
+                            "type": "string",
+                            "default": "desc",
+                            "enum": [
+                                "asc",
+                                "desc"
+                            ],
+                            "required": false
+                        },
+                        "orderby": {
+                            "description": "Sort collection by object attribute.",
+                            "type": "string",
+                            "default": "date",
+                            "enum": [
+                                "date",
+                                "id",
+                                "include",
+                                "relevance",
+                                "slug",
+                                "include_slugs",
+                                "title"
+                            ],
+                            "required": false
+                        }
+                    }
+                }
+            ]
+        },
+        "/wp/v2/template-parts/(?P<parent>[\\d]+)/revisions/(?P<id>[\\d]+)": {
+            "namespace": "wp/v2",
+            "methods": [
+                "GET",
+                "DELETE"
+            ],
+            "endpoints": [
+                {
+                    "methods": [
+                        "GET"
+                    ],
+                    "args": {
+                        "parent": {
+                            "description": "The ID for the parent of the revision.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "id": {
+                            "description": "Unique identifier for the revision.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "context": {
+                            "description": "Scope under which the request is made; determines fields present in response.",
+                            "type": "string",
+                            "enum": [
+                                "view",
+                                "embed",
+                                "edit"
+                            ],
+                            "default": "view",
+                            "required": false
+                        }
+                    }
+                },
+                {
+                    "methods": [
+                        "DELETE"
+                    ],
+                    "args": {
+                        "parent": {
+                            "description": "The ID for the parent of the revision.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "id": {
+                            "description": "Unique identifier for the revision.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "force": {
+                            "type": "boolean",
+                            "default": false,
+                            "description": "Required to be true, as revisions do not support trashing.",
+                            "required": false
+                        }
+                    }
+                }
+            ]
+        },
+        "/wp/v2/template-parts/(?P<id>[\\d]+)/autosaves": {
+            "namespace": "wp/v2",
+            "methods": [
+                "GET",
+                "POST"
+            ],
+            "endpoints": [
+                {
+                    "methods": [
+                        "GET"
+                    ],
+                    "args": {
+                        "parent": {
+                            "description": "The ID for the parent of the autosave.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "context": {
+                            "description": "Scope under which the request is made; determines fields present in response.",
+                            "type": "string",
+                            "enum": [
+                                "view",
+                                "embed",
+                                "edit"
+                            ],
+                            "default": "view",
+                            "required": false
+                        }
+                    }
+                },
+                {
+                    "methods": [
+                        "POST"
+                    ],
+                    "args": {
+                        "parent": {
+                            "description": "The ID for the parent of the autosave.",
+                            "type": "integer",
+                            "required": false
+                        },
+                        "slug": {
+                            "description": "Unique slug identifying the template.",
+                            "type": "string",
+                            "minLength": 1,
+                            "pattern": "[a-zA-Z_\\-]+",
+                            "required": false
+                        },
+                        "theme": {
+                            "description": "Theme identifier for the template.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "content": {
+                            "description": "Content of template.",
+                            "type": [
+                                "object",
+                                "string"
+                            ],
+                            "required": false
+                        },
+                        "title": {
+                            "description": "Title of template.",
+                            "type": [
+                                "object",
+                                "string"
+                            ],
+                            "required": false
+                        },
+                        "description": {
+                            "description": "Description of template.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "status": {
+                            "description": "Status of template.",
+                            "type": "string",
+                            "required": false
+                        },
+                        "area": {
+                            "description": "Where the template part is intended for use (header, footer, etc.)",
+                            "type": "string",
+                            "required": false
+                        }
+                    }
+                }
+            ]
+        },
+        "/wp/v2/template-parts/(?P<parent>[\\d]+)/autosaves/(?P<id>[\\d]+)": {
             "namespace": "wp/v2",
             "methods": [
@@ -8611 +9093 @@
             ]
         }
+    },
+    "wp_template_part": {
+        "description": "Template parts to include in your templates.",
+        "hierarchical": false,
+        "name": "Template Parts",
+        "slug": "wp_template_part",
+        "taxonomies": [],
+        "rest_base": "template-parts",
+        "rest_namespace": "wp/v2",
+        "_links": {
+            "collection": [
+                {
+                    "href": "http://example.org/index.php?rest_route=/wp/v2/types"
+                }
+            ],
+            "wp:items": [
+                {
+                    "href": "http://example.org/index.php?rest_route=/wp/v2/template-parts"
+                }
+            ],
+            "curies": [
+                {
+                    "name": "wp",
+                    "href": "https://api.w.org/{rel}",
+                    "templated": true
+                }
+            ]
+        }
     }
 };

trunk/tools/webpack/blocks.js

@@ -54 +54 @@
                 'social-link',
                 'tag-cloud',
+                'template-part',
         ];
         const blockFolders = [