From 2d3f7348477b5d721ff5cf5c04c886af2f61129c Mon Sep 17 00:00:00 2001
From: Gary Pendergast <gary@pento.net>
Date: Thu, 13 Dec 2018 09:44:23 +0000
Subject: [PATCH] Blocks: Introduce `WP_Block_Type` and
 `WP_Block_Type_Registry` classes.

These are the foundational classes allowing blocks to be registered and used throughout WordPress.

This commit also includes the `has_block()` and `has_blocks()` functions, which are required for unit testing these classes.

Merges [43742] from the 5.0 branch to trunk.

Props adamsilverstein, danielbachhuber, desrosj.
Fixes #45097.
See #45109.

Built from https://develop.svn.wordpress.org/trunk@44108


git-svn-id: http://core.svn.wordpress.org/trunk@43938 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/blocks.php                       |  61 ++++++
 wp-includes/class-wp-block-type-registry.php | 173 ++++++++++++++++
 wp-includes/class-wp-block-type.php          | 205 +++++++++++++++++++
 wp-includes/version.php                      |   2 +-
 wp-settings.php                              |   3 +
 5 files changed, 443 insertions(+), 1 deletion(-)
 create mode 100644 wp-includes/blocks.php
 create mode 100644 wp-includes/class-wp-block-type-registry.php
 create mode 100644 wp-includes/class-wp-block-type.php

diff --git a/wp-includes/blocks.php b/wp-includes/blocks.php
new file mode 100644
index 0000000000..b04696d591
--- /dev/null
+++ b/wp-includes/blocks.php
@@ -0,0 +1,61 @@
+<?php
+/**
+ * Functions related to registering and parsing blocks.
+ *
+ * @package WordPress
+ * @subpackage Blocks
+ * @since 5.0.0
+ */
+
+/**
+ * Determine whether a post or content string has blocks.
+ *
+ * This test optimizes for performance rather than strict accuracy, detecting
+ * the pattern of a block but not validating its structure. For strict accuracy,
+ * you should use the block parser on post content.
+ *
+ * @since 5.0.0
+ * @see parse_blocks()
+ *
+ * @param int|string|WP_Post|null $post Optional. Post content, post ID, or post object. Defaults to global $post.
+ * @return bool Whether the post has blocks.
+ */
+function has_blocks( $post = null ) {
+	if ( ! is_string( $post ) ) {
+		$wp_post = get_post( $post );
+		if ( $wp_post instanceof WP_Post ) {
+			$post = $wp_post->post_content;
+		}
+	}
+
+	return false !== strpos( (string) $post, '<!-- wp:' );
+}
+
+/**
+ * Determine whether a $post or a string contains a specific block type.
+ *
+ * This test optimizes for performance rather than strict accuracy, detecting
+ * the block type exists but not validating its structure. For strict accuracy,
+ * you should use the block parser on post content.
+ *
+ * @since 5.0.0
+ * @see parse_blocks()
+ *
+ * @param string                  $block_type Full Block type to look for.
+ * @param int|string|WP_Post|null $post Optional. Post content, post ID, or post object. Defaults to global $post.
+ * @return bool Whether the post content contains the specified block.
+ */
+function has_block( $block_type, $post = null ) {
+	if ( ! has_blocks( $post ) ) {
+		return false;
+	}
+
+	if ( ! is_string( $post ) ) {
+		$wp_post = get_post( $post );
+		if ( $wp_post instanceof WP_Post ) {
+			$post = $wp_post->post_content;
+		}
+	}
+
+	return false !== strpos( $post, '<!-- wp:' . $block_type . ' ' );
+}
diff --git a/wp-includes/class-wp-block-type-registry.php b/wp-includes/class-wp-block-type-registry.php
new file mode 100644
index 0000000000..d8894e6abe
--- /dev/null
+++ b/wp-includes/class-wp-block-type-registry.php
@@ -0,0 +1,173 @@
+<?php
+/**
+ * Blocks API: WP_Block_Type_Registry class
+ *
+ * @package WordPress
+ * @subpackage Blocks
+ * @since 5.0.0
+ */
+
+/**
+ * Core class used for interacting with block types.
+ *
+ * @since 5.0.0
+ */
+final class WP_Block_Type_Registry {
+	/**
+	 * Registered block types, as `$name => $instance` pairs.
+	 *
+	 * @since 5.0.0
+	 * @var WP_Block_Type[]
+	 */
+	private $registered_block_types = array();
+
+	/**
+	 * Container for the main instance of the class.
+	 *
+	 * @since 5.0.0
+	 * @var WP_Block_Type_Registry|null
+	 */
+	private static $instance = null;
+
+	/**
+	 * Registers a block type.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param string|WP_Block_Type $name Block type name including namespace, or alternatively a
+	 *                                   complete WP_Block_Type instance. In case a WP_Block_Type
+	 *                                   is provided, the $args parameter will be ignored.
+	 * @param array                $args {
+	 *     Optional. Array of block type arguments. Any arguments may be defined, however the
+	 *     ones described below are supported by default. Default empty array.
+	 *
+	 *     @type callable $render_callback Callback used to render blocks of this block type.
+	 *     @type array    $attributes      Block attributes mapping, property name to schema.
+	 * }
+	 * @return WP_Block_Type|false The registered block type on success, or false on failure.
+	 */
+	public function register( $name, $args = array() ) {
+		$block_type = null;
+		if ( $name instanceof WP_Block_Type ) {
+			$block_type = $name;
+			$name       = $block_type->name;
+		}
+
+		if ( ! is_string( $name ) ) {
+			$message = __( 'Block type names must be strings.' );
+			_doing_it_wrong( __METHOD__, $message, '5.0.0' );
+			return false;
+		}
+
+		if ( preg_match( '/[A-Z]+/', $name ) ) {
+			$message = __( 'Block type names must not contain uppercase characters.' );
+			_doing_it_wrong( __METHOD__, $message, '5.0.0' );
+			return false;
+		}
+
+		$name_matcher = '/^[a-z0-9-]+\/[a-z0-9-]+$/';
+		if ( ! preg_match( $name_matcher, $name ) ) {
+			$message = __( 'Block type names must contain a namespace prefix. Example: my-plugin/my-custom-block-type' );
+			_doing_it_wrong( __METHOD__, $message, '5.0.0' );
+			return false;
+		}
+
+		if ( $this->is_registered( $name ) ) {
+			/* translators: %s: block name */
+			$message = sprintf( __( 'Block type "%s" is already registered.' ), $name );
+			_doing_it_wrong( __METHOD__, $message, '5.0.0' );
+			return false;
+		}
+
+		if ( ! $block_type ) {
+			$block_type = new WP_Block_Type( $name, $args );
+		}
+
+		$this->registered_block_types[ $name ] = $block_type;
+
+		return $block_type;
+	}
+
+	/**
+	 * Unregisters a block type.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param string|WP_Block_Type $name Block type name including namespace, or alternatively a
+	 *                                   complete WP_Block_Type instance.
+	 * @return WP_Block_Type|false The unregistered block type on success, or false on failure.
+	 */
+	public function unregister( $name ) {
+		if ( $name instanceof WP_Block_Type ) {
+			$name = $name->name;
+		}
+
+		if ( ! $this->is_registered( $name ) ) {
+			/* translators: %s: block name */
+			$message = sprintf( __( 'Block type "%s" is not registered.' ), $name );
+			_doing_it_wrong( __METHOD__, $message, '5.0.0' );
+			return false;
+		}
+
+		$unregistered_block_type = $this->registered_block_types[ $name ];
+		unset( $this->registered_block_types[ $name ] );
+
+		return $unregistered_block_type;
+	}
+
+	/**
+	 * Retrieves a registered block type.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param string $name Block type name including namespace.
+	 * @return WP_Block_Type|null The registered block type, or null if it is not registered.
+	 */
+	public function get_registered( $name ) {
+		if ( ! $this->is_registered( $name ) ) {
+			return null;
+		}
+
+		return $this->registered_block_types[ $name ];
+	}
+
+	/**
+	 * Retrieves all registered block types.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @return WP_Block_Type[] Associative array of `$block_type_name => $block_type` pairs.
+	 */
+	public function get_all_registered() {
+		return $this->registered_block_types;
+	}
+
+	/**
+	 * Checks if a block type is registered.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param string $name Block type name including namespace.
+	 * @return bool True if the block type is registered, false otherwise.
+	 */
+	public function is_registered( $name ) {
+		return isset( $this->registered_block_types[ $name ] );
+	}
+
+	/**
+	 * Utility method to retrieve the main instance of the class.
+	 *
+	 * The instance will be created if it does not exist yet.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @return WP_Block_Type_Registry The main instance.
+	 */
+	public static function get_instance() {
+		if ( null === self::$instance ) {
+			self::$instance = new self();
+		}
+
+		return self::$instance;
+	}
+}
diff --git a/wp-includes/class-wp-block-type.php b/wp-includes/class-wp-block-type.php
new file mode 100644
index 0000000000..4247cccffa
--- /dev/null
+++ b/wp-includes/class-wp-block-type.php
@@ -0,0 +1,205 @@
+<?php
+/**
+ * Blocks API: WP_Block_Type class
+ *
+ * @package WordPress
+ * @subpackage Blocks
+ * @since 5.0.0
+ */
+
+/**
+ * Core class representing a block type.
+ *
+ * @since 5.0.0
+ *
+ * @see register_block_type()
+ */
+class WP_Block_Type {
+	/**
+	 * Block type key.
+	 *
+	 * @since 5.0.0
+	 * @var string
+	 */
+	public $name;
+
+	/**
+	 * Block type render callback.
+	 *
+	 * @since 5.0.0
+	 * @var callable
+	 */
+	public $render_callback;
+
+	/**
+	 * Block type attributes property schemas.
+	 *
+	 * @since 5.0.0
+	 * @var array
+	 */
+	public $attributes;
+
+	/**
+	 * Block type editor script handle.
+	 *
+	 * @since 5.0.0
+	 * @var string
+	 */
+	public $editor_script;
+
+	/**
+	 * Block type front end script handle.
+	 *
+	 * @since 5.0.0
+	 * @var string
+	 */
+	public $script;
+
+	/**
+	 * Block type editor style handle.
+	 *
+	 * @since 5.0.0
+	 * @var string
+	 */
+	public $editor_style;
+
+	/**
+	 * Block type front end style handle.
+	 *
+	 * @since 5.0.0
+	 * @var string
+	 */
+	public $style;
+
+	/**
+	 * Constructor.
+	 *
+	 * Will populate object properties from the provided arguments.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @see register_block_type()
+	 *
+	 * @param string       $block_type Block type name including namespace.
+	 * @param array|string $args       Optional. Array or string of arguments for registering a block type.
+	 *                                 Default empty array.
+	 */
+	public function __construct( $block_type, $args = array() ) {
+		$this->name = $block_type;
+
+		$this->set_props( $args );
+	}
+
+	/**
+	 * Renders the block type output for given attributes.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param array  $attributes Optional. Block attributes. Default empty array.
+	 * @param string $content    Optional. Block content. Default empty string.
+	 * @return string Rendered block type output.
+	 */
+	public function render( $attributes = array(), $content = '' ) {
+		if ( ! $this->is_dynamic() ) {
+			return '';
+		}
+
+		$attributes = $this->prepare_attributes_for_render( $attributes );
+
+		return (string) call_user_func( $this->render_callback, $attributes, $content );
+	}
+
+	/**
+	 * Returns true if the block type is dynamic, or false otherwise. A dynamic
+	 * block is one which defers its rendering to occur on-demand at runtime.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @return boolean Whether block type is dynamic.
+	 */
+	public function is_dynamic() {
+		return is_callable( $this->render_callback );
+	}
+
+	/**
+	 * Validates attributes against the current block schema, populating
+	 * defaulted and missing values, and omitting unknown attributes.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param  array $attributes Original block attributes.
+	 * @return array             Prepared block attributes.
+	 */
+	public function prepare_attributes_for_render( $attributes ) {
+		if ( ! isset( $this->attributes ) ) {
+			return $attributes;
+		}
+
+		$prepared_attributes = array();
+
+		foreach ( $this->attributes as $attribute_name => $schema ) {
+			$value = null;
+
+			if ( isset( $attributes[ $attribute_name ] ) ) {
+				$is_valid = rest_validate_value_from_schema( $attributes[ $attribute_name ], $schema );
+				if ( ! is_wp_error( $is_valid ) ) {
+					$value = rest_sanitize_value_from_schema( $attributes[ $attribute_name ], $schema );
+				}
+			}
+
+			if ( is_null( $value ) && isset( $schema['default'] ) ) {
+				$value = $schema['default'];
+			}
+
+			$prepared_attributes[ $attribute_name ] = $value;
+		}
+
+		return $prepared_attributes;
+	}
+
+	/**
+	 * Sets block type properties.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param array|string $args Array or string of arguments for registering a block type.
+	 */
+	public function set_props( $args ) {
+		$args = wp_parse_args(
+			$args,
+			array(
+				'render_callback' => null,
+			)
+		);
+
+		$args['name'] = $this->name;
+
+		foreach ( $args as $property_name => $property_value ) {
+			$this->$property_name = $property_value;
+		}
+	}
+
+	/**
+	 * Get all available block attributes including possible layout attribute from Columns block.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @return array Array of attributes.
+	 */
+	public function get_attributes() {
+		return is_array( $this->attributes ) ?
+			array_merge(
+				$this->attributes,
+				array(
+					'layout' => array(
+						'type' => 'string',
+					),
+				)
+			) :
+			array(
+				'layout' => array(
+					'type' => 'string',
+				),
+			);
+	}
+}
diff --git a/wp-includes/version.php b/wp-includes/version.php
index eba953f756..9ed74b60d7 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.1-alpha-44107';
+$wp_version = '5.1-alpha-44108';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.
diff --git a/wp-settings.php b/wp-settings.php
index 6e93f7b6e8..4ae30df9ca 100644
--- a/wp-settings.php
+++ b/wp-settings.php
@@ -244,6 +244,9 @@ require( ABSPATH . WPINC . '/rest-api/fields/class-wp-rest-term-meta-fields.php'
 require( ABSPATH . WPINC . '/rest-api/fields/class-wp-rest-user-meta-fields.php' );
 require( ABSPATH . WPINC . '/rest-api/search/class-wp-rest-search-handler.php' );
 require( ABSPATH . WPINC . '/rest-api/search/class-wp-rest-post-search-handler.php' );
+require( ABSPATH . WPINC . '/class-wp-block-type.php' );
+require( ABSPATH . WPINC . '/class-wp-block-type-registry.php' );
+require( ABSPATH . WPINC . '/blocks.php' );
 
 $GLOBALS['wp_embed'] = new WP_Embed();