diff -r c7c34916027a -r 177826044cd9 wp/wp-includes/blocks.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-includes/blocks.php	Mon Oct 14 18:28:13 2019 +0200
@@ -0,0 +1,359 @@
+<?php
+/**
+ * Functions related to registering and parsing blocks.
+ *
+ * @package WordPress
+ * @subpackage Blocks
+ * @since 5.0.0
+ */
+
+/**
+ * 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.
+ * }
+ * @return WP_Block_Type|false The registered block type on success, or false on failure.
+ */
+function register_block_type( $name, $args = array() ) {
+	return WP_Block_Type_Registry::get_instance()->register( $name, $args );
+}
+
+/**
+ * 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.
+ */
+function unregister_block_type( $name ) {
+	return WP_Block_Type_Registry::get_instance()->unregister( $name );
+}
+
+/**
+ * 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 . ' ' );
+}
+
+/**
+ * Returns an array of the names of all registered dynamic block types.
+ *
+ * @since 5.0.0
+ *
+ * @return array Array of dynamic block names.
+ */
+function get_dynamic_block_names() {
+	$dynamic_block_names = array();
+
+	$block_types = WP_Block_Type_Registry::get_instance()->get_all_registered();
+	foreach ( $block_types as $block_type ) {
+		if ( $block_type->is_dynamic() ) {
+			$dynamic_block_names[] = $block_type->name;
+		}
+	}
+
+	return $dynamic_block_names;
+}
+
+/**
+ * Parses blocks out of a content string, and renders those appropriate for the excerpt.
+ *
+ * As the excerpt should be a small string of text relevant to the full post content,
+ * this function renders the blocks that are most likely to contain such text.
+ *
+ * @since 5.0.0
+ *
+ * @param string $content The content to parse.
+ * @return string The parsed and filtered content.
+ */
+function excerpt_remove_blocks( $content ) {
+	$allowed_inner_blocks = array(
+		// Classic blocks have their blockName set to null.
+		null,
+		'core/freeform',
+		'core/heading',
+		'core/html',
+		'core/list',
+		'core/media-text',
+		'core/paragraph',
+		'core/preformatted',
+		'core/pullquote',
+		'core/quote',
+		'core/table',
+		'core/verse',
+	);
+
+	$allowed_blocks = array_merge( $allowed_inner_blocks, array( 'core/columns' ) );
+
+	/**
+	 * Filters the list of blocks that can contribute to the excerpt.
+	 *
+	 * If a dynamic block is added to this list, it must not generate another
+	 * excerpt, as this will cause an infinite loop to occur.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param array $allowed_blocks The list of allowed blocks.
+	 */
+	$allowed_blocks = apply_filters( 'excerpt_allowed_blocks', $allowed_blocks );
+	$blocks         = parse_blocks( $content );
+	$output         = '';
+
+	foreach ( $blocks as $block ) {
+		if ( in_array( $block['blockName'], $allowed_blocks, true ) ) {
+			if ( ! empty( $block['innerBlocks'] ) ) {
+				if ( 'core/columns' === $block['blockName'] ) {
+					$output .= _excerpt_render_inner_columns_blocks( $block, $allowed_inner_blocks );
+					continue;
+				}
+
+				// Skip the block if it has disallowed or nested inner blocks.
+				foreach ( $block['innerBlocks'] as $inner_block ) {
+					if (
+						! in_array( $inner_block['blockName'], $allowed_inner_blocks, true ) ||
+						! empty( $inner_block['innerBlocks'] )
+					) {
+						continue 2;
+					}
+				}
+			}
+
+			$output .= render_block( $block );
+		}
+	}
+
+	return $output;
+}
+
+/**
+ * Render inner blocks from the `core/columns` block for generating an excerpt.
+ *
+ * @since 5.2.0
+ * @access private
+ *
+ * @param array $columns        The parsed columns block.
+ * @param array $allowed_blocks The list of allowed inner blocks.
+ * @return string The rendered inner blocks.
+ */
+function _excerpt_render_inner_columns_blocks( $columns, $allowed_blocks ) {
+	$output = '';
+
+	foreach ( $columns['innerBlocks'] as $column ) {
+		foreach ( $column['innerBlocks'] as $inner_block ) {
+			if ( in_array( $inner_block['blockName'], $allowed_blocks, true ) && empty( $inner_block['innerBlocks'] ) ) {
+				$output .= render_block( $inner_block );
+			}
+		}
+	}
+
+	return $output;
+}
+
+/**
+ * Renders a single block into a HTML string.
+ *
+ * @since 5.0.0
+ *
+ * @global WP_Post $post The post to edit.
+ *
+ * @param array $block A single parsed block object.
+ * @return string String of rendered HTML.
+ */
+function render_block( $block ) {
+	global $post;
+
+	/**
+	 * Allows render_block() to be shortcircuited, by returning a non-null value.
+	 *
+	 * @since 5.1.0
+	 *
+	 * @param string $pre_render The pre-rendered content. Default null.
+	 * @param array  $block      The block being rendered.
+	 */
+	$pre_render = apply_filters( 'pre_render_block', null, $block );
+	if ( ! is_null( $pre_render ) ) {
+		return $pre_render;
+	}
+
+	$source_block = $block;
+
+	/**
+	 * Filters the block being rendered in render_block(), before it's processed.
+	 *
+	 * @since 5.1.0
+	 *
+	 * @param array $block        The block being rendered.
+	 * @param array $source_block An un-modified copy of $block, as it appeared in the source content.
+	 */
+	$block = apply_filters( 'render_block_data', $block, $source_block );
+
+	$block_type    = WP_Block_Type_Registry::get_instance()->get_registered( $block['blockName'] );
+	$is_dynamic    = $block['blockName'] && null !== $block_type && $block_type->is_dynamic();
+	$block_content = '';
+	$index         = 0;
+
+	foreach ( $block['innerContent'] as $chunk ) {
+		$block_content .= is_string( $chunk ) ? $chunk : render_block( $block['innerBlocks'][ $index++ ] );
+	}
+
+	if ( ! is_array( $block['attrs'] ) ) {
+		$block['attrs'] = array();
+	}
+
+	if ( $is_dynamic ) {
+		$global_post   = $post;
+		$block_content = $block_type->render( $block['attrs'], $block_content );
+		$post          = $global_post;
+	}
+
+	/**
+	 * Filters the content of a single block.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param string $block_content The block content about to be appended.
+	 * @param array  $block         The full block, including name and attributes.
+	 */
+	return apply_filters( 'render_block', $block_content, $block );
+}
+
+/**
+ * Parses blocks out of a content string.
+ *
+ * @since 5.0.0
+ *
+ * @param string $content Post content.
+ * @return array Array of parsed block objects.
+ */
+function parse_blocks( $content ) {
+	/**
+	 * Filter to allow plugins to replace the server-side block parser
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param string $parser_class Name of block parser class.
+	 */
+	$parser_class = apply_filters( 'block_parser_class', 'WP_Block_Parser' );
+
+	$parser = new $parser_class();
+	return $parser->parse( $content );
+}
+
+/**
+ * Parses dynamic blocks out of `post_content` and re-renders them.
+ *
+ * @since 5.0.0
+ * @global WP_Post $post The post to edit.
+ *
+ * @param  string $content Post content.
+ * @return string Updated post content.
+ */
+function do_blocks( $content ) {
+	$blocks = parse_blocks( $content );
+	$output = '';
+
+	foreach ( $blocks as $block ) {
+		$output .= render_block( $block );
+	}
+
+	// If there are blocks in this content, we shouldn't run wpautop() on it later.
+	$priority = has_filter( 'the_content', 'wpautop' );
+	if ( false !== $priority && doing_filter( 'the_content' ) && has_blocks( $content ) ) {
+		remove_filter( 'the_content', 'wpautop', $priority );
+		add_filter( 'the_content', '_restore_wpautop_hook', $priority + 1 );
+	}
+
+	return $output;
+}
+
+/**
+ * If do_blocks() needs to remove wpautop() from the `the_content` filter, this re-adds it afterwards,
+ * for subsequent `the_content` usage.
+ *
+ * @access private
+ *
+ * @since 5.0.0
+ *
+ * @param string $content The post content running through this filter.
+ * @return string The unmodified content.
+ */
+function _restore_wpautop_hook( $content ) {
+	$current_priority = has_filter( 'the_content', '_restore_wpautop_hook' );
+
+	add_filter( 'the_content', 'wpautop', $current_priority - 1 );
+	remove_filter( 'the_content', '_restore_wpautop_hook', $current_priority );
+
+	return $content;
+}
+
+/**
+ * Returns the current version of the block format that the content string is using.
+ *
+ * If the string doesn't contain blocks, it returns 0.
+ *
+ * @since 5.0.0
+ *
+ * @param string $content Content to test.
+ * @return int The block format version is 1 if the content contains one or more blocks, 0 otherwise.
+ */
+function block_version( $content ) {
+	return has_blocks( $content ) ? 1 : 0;
+}