JezK
Edit File: custom-css.php
<?php /** * Custom CSS block support. * * @package WordPress */ /** * Render the custom CSS stylesheet and add class name to block as required. * * @since 7.0.0 * * @param array $parsed_block The parsed block. * @return array The same parsed block with custom CSS class name added if appropriate. * * @phpstan-param array{ * blockName: string|null, * attrs: array{ * className?: string, * style?: array{ * css?: string, * ... * }, * ... * }, * ... * } $parsed_block * @phpstan-return array{ * blockName: string|null, * attrs: array{ * className?: string, * style?: array{ * css?: string, * ... * }, * ... * }, * ... * } */ function wp_render_custom_css_support_styles( $parsed_block ) { $custom_css = $parsed_block['attrs']['style']['css'] ?? null; if ( ! is_string( $custom_css ) || '' === trim( $custom_css ) ) { return $parsed_block; } $block_type = WP_Block_Type_Registry::get_instance()->get_registered( $parsed_block['blockName'] ); if ( ! block_has_support( $block_type, 'customCSS', true ) ) { return $parsed_block; } // Validate CSS doesn't contain HTML markup (same validation as global styles REST API). if ( preg_match( '#</?\w+#', $custom_css ) ) { return $parsed_block; } // Generate a unique class name for this block instance. $class_name = wp_unique_id_from_values( $parsed_block, 'wp-custom-css-' ); $existing_class_name = $parsed_block['attrs']['className'] ?? null; $updated_class_name = is_string( $existing_class_name ) ? "$existing_class_name $class_name" : $class_name; $parsed_block['attrs']['className'] = $updated_class_name; // Process the custom CSS using the same method as global styles. $selector = '.' . $class_name; $processed_css = WP_Theme_JSON::process_blocks_custom_css( $custom_css, $selector ); if ( ! empty( $processed_css ) ) { /** * Reuse one handle so identical custom CSS is enqueued only once via * {@see wp_unique_id_from_values()}. Explicitly declare the `wp-block-library` * dependency so `global-styles` is guaranteed to print after it, preventing * block default styles from unintentionally overriding global styles. */ $handle = 'wp-block-custom-css'; if ( ! wp_style_is( $handle, 'registered' ) ) { wp_register_style( $handle, false, array( 'wp-block-library', 'global-styles' ) ); } $after_styles = wp_styles()->get_data( $handle, 'after' ); if ( ! is_array( $after_styles ) ) { $after_styles = array(); } if ( ! in_array( $processed_css, $after_styles, true ) ) { wp_add_inline_style( $handle, $processed_css ); } } return $parsed_block; } /** * Enqueues the block custom CSS styles. * * @since 7.0.0 */ function wp_enqueue_block_custom_css() { wp_enqueue_style( 'wp-block-custom-css' ); } /** * Applies the custom CSS class name to the block's rendered HTML. * * The class name is generated in {@see wp_render_custom_css_support_styles()} * and stored in block attributes. This filter adds it to the actual markup. * * @since 7.0.0 * * @param string $block_content Rendered block content. * @param array $block Block object. * @return string Filtered block content. * * @phpstan-param array{ * attrs: array{ * className?: string, * ... * }, * ... * } $block */ function wp_render_custom_css_class_name( $block_content, $block ) { $class_name_attr = $block['attrs']['className'] ?? null; $class_name_prefix = 'wp-custom-css-'; if ( ! is_string( $class_name_attr ) || ! str_contains( $class_name_attr, $class_name_prefix ) ) { return $block_content; } // Parse out the 'wp-custom-css-*' class name added by wp_render_custom_css_support_styles(). $matched_class_name = null; $token_delimiter = " \t\f\r\n"; $class_token = strtok( $class_name_attr, $token_delimiter ); while ( false !== $class_token ) { if ( str_starts_with( $class_token, $class_name_prefix ) ) { $matched_class_name = $class_token; break; } $class_token = strtok( $token_delimiter ); } if ( null === $matched_class_name ) { return $block_content; } $tags = new WP_HTML_Tag_Processor( $block_content ); if ( $tags->next_tag() ) { $tags->add_class( 'has-custom-css' ); $tags->add_class( $matched_class_name ); } return $tags->get_updated_html(); } add_filter( 'render_block', 'wp_render_custom_css_class_name', 10, 2 ); add_filter( 'render_block_data', 'wp_render_custom_css_support_styles', 10, 1 ); add_action( 'wp_enqueue_scripts', 'wp_enqueue_block_custom_css', 1 ); /** * Registers the style block attribute for block types that support it. * * @param WP_Block_Type $block_type Block Type. */ function wp_register_custom_css_support( $block_type ) { // Setup attributes and styles within that if needed. if ( ! $block_type->attributes ) { $block_type->attributes = array(); } // Check for existing style attribute definition e.g. from block.json. if ( array_key_exists( 'style', $block_type->attributes ) ) { return; } $has_custom_css_support = block_has_support( $block_type, array( 'customCSS' ), true ); if ( $has_custom_css_support ) { $block_type->attributes['style'] = array( 'type' => 'object', ); } } /** * Strips custom CSS (`style.css` in attributes) from all blocks in post content. * * Uses {@see WP_Block_Parser::next_token()} to scan block tokens and surgically * replace only the attribute JSON that changed — no parse_blocks() + * serialize_blocks() round-trip needed. * * @since 7.0.0 * @access private * * @param string $content Post content to filter, expected to be escaped with slashes. * @return string Filtered post content with block custom CSS removed. */ function wp_strip_custom_css_from_blocks( $content ) { if ( ! has_blocks( $content ) ) { return $content; } $unslashed = stripslashes( $content ); $parser = new WP_Block_Parser(); $parser->document = $unslashed; $parser->offset = 0; $end = strlen( $unslashed ); $replacements = array(); while ( $parser->offset < $end ) { $next_token = $parser->next_token(); if ( 'no-more-tokens' === $next_token[0] ) { break; } list( $token_type, , $attrs, $start_offset, $token_length ) = $next_token; $parser->offset = $start_offset + $token_length; if ( 'block-opener' !== $token_type && 'void-block' !== $token_type ) { continue; } if ( ! isset( $attrs['style']['css'] ) ) { continue; } // Remove css and clean up empty style. unset( $attrs['style']['css'] ); if ( empty( $attrs['style'] ) ) { unset( $attrs['style'] ); } // Locate the JSON portion within the token. $token_string = substr( $unslashed, $start_offset, $token_length ); $json_rel_start = strcspn( $token_string, '{' ); $json_rel_end = strrpos( $token_string, '}' ); $json_start = $start_offset + $json_rel_start; $json_length = $json_rel_end - $json_rel_start + 1; // Re-encode attributes. If attrs is now empty, remove JSON and trailing space. if ( empty( $attrs ) ) { // Remove the trailing space after JSON. $replacements[] = array( $json_start, $json_length + 1, '' ); } else { $replacements[] = array( $json_start, $json_length, serialize_block_attributes( $attrs ) ); } } if ( empty( $replacements ) ) { return $content; } // Build the result by splicing replacements into the original string. $result = ''; $was_at = 0; foreach ( $replacements as $replacement ) { list( $offset, $length, $new_json ) = $replacement; $result .= substr( $unslashed, $was_at, $offset - $was_at ) . $new_json; $was_at = $offset + $length; } if ( $was_at < $end ) { $result .= substr( $unslashed, $was_at ); } return addslashes( $result ); } /** * Adds the filters to strip custom CSS from block content on save. * Priority of 8 to run before wp_filter_global_styles_post (priority 9) and wp_filter_post_kses (priority 10). * * @since 7.0.0 * @access private */ function wp_custom_css_kses_init_filters() { add_filter( 'content_save_pre', 'wp_strip_custom_css_from_blocks', 8 ); add_filter( 'content_filtered_save_pre', 'wp_strip_custom_css_from_blocks', 8 ); } /** * Removes the filters that strip custom CSS from block content on save. * Priority of 8 to run before wp_filter_global_styles_post (priority 9) and wp_filter_post_kses (priority 10). * * @since 7.0.0 * @access private */ function wp_custom_css_remove_filters() { remove_filter( 'content_save_pre', 'wp_strip_custom_css_from_blocks', 8 ); remove_filter( 'content_filtered_save_pre', 'wp_strip_custom_css_from_blocks', 8 ); } /** * Registers the custom CSS content filters if the user does not have the edit_css capability. * * @since 7.0.0 * @access private */ function wp_custom_css_kses_init() { wp_custom_css_remove_filters(); if ( ! current_user_can( 'edit_css' ) ) { wp_custom_css_kses_init_filters(); } } /** * Initializes custom CSS content filters when imported data should be filtered. * * Runs at priority 999 on {@see 'force_filtered_html_on_import'} to ensure it * fires after general KSES initialization, independently of user capabilities. * If the input of the filter is true it means we are in an import situation and should * enable the custom CSS filters, independently of the user capabilities. * * @since 7.0.0 * @access private * * @param mixed $arg Input argument of the filter. * @return mixed Input argument of the filter. */ function wp_custom_css_force_filtered_html_on_import_filter( $arg ) { if ( $arg ) { wp_custom_css_kses_init_filters(); } return $arg; } // Run before wp_filter_global_styles_post (priority 9) and wp_filter_post_kses (priority 10). add_action( 'init', 'wp_custom_css_kses_init', 20 ); add_action( 'set_current_user', 'wp_custom_css_kses_init' ); add_filter( 'force_filtered_html_on_import', 'wp_custom_css_force_filtered_html_on_import_filter', 999 ); // Register the block support. WP_Block_Supports::get_instance()->register( 'custom-css', array( 'register_attribute' => 'wp_register_custom_css_support', ) );