Don't split on commas

Author: t-hamano

src/wp-includes/class-wp-block-supports.php

@@ -193,10 +193,10 @@ function get_block_wrapper_attributes( $extra_attributes = array() ) {
 		},
 		'class'      => static function ( $new_attribute, $extra_attribute ) {
 			$classes = array_merge(
-				wp_parse_list( $extra_attribute ),
-				wp_parse_list( $new_attribute )
+				preg_split( '/\s+/', $extra_attribute, -1, PREG_SPLIT_NO_EMPTY ),
+				preg_split( '/\s+/', $new_attribute, -1, PREG_SPLIT_NO_EMPTY )
 			);
-			$classes = array_unique( array_filter( array_map( 'sanitize_html_class', $classes ) ) );
+			$classes = array_unique( array_filter( $classes ) );
 			return implode( ' ', $classes );
 		},
 		'id'         => static function ( $new_attribute, $extra_attribute ) {

tests/phpunit/tests/blocks/supportedStyles.php

@@ -837,10 +837,10 @@ public function data_get_block_wrapper_attributes_merge_or_override() {
 						),
 					),
 					'extra_attributes'    => array(
-						// Duplicate class names should be merged
-						'class' => 'extra-class has-text-color',
+						// Duplicate class names should be merged, and commas should be preserved.
+						'class' => 'extra-class extra,class has-text-color',
 					),
-					'expected_attribute'  => 'class="extra-class has-text-color wp-block-example"',
+					'expected_attribute'  => 'class="extra-class extra,class has-text-color wp-block-example"',
 				),
 			),
 			'extra attributes override block-generated id' => array(