: str_replace(): Passing null to parameter #2 ($replace) of type array|string is deprecated in
namespace Yoast\WP\SEO\Helpers\Schema;
* Sanitizes a HTML string by stripping all tags except headings, breaks, lists, links, paragraphs and formatting.
* @param string $html The original HTML.
* @return string The sanitized HTML.
public function sanitize( $html ) {
if ( ! $this->is_non_empty_string_or_stringable( $html ) ) {
if ( \is_int( $html ) || \is_float( $html ) ) {
return \strip_tags( $html, '<h1><h2><h3><h4><h5><h6><br><ol><ul><li><a><p><b><strong><i><em>' );
* Strips the tags in a smart way.
* @param string $html The original HTML.
* @return string The sanitized HTML.
public function smart_strip_tags( $html ) {
if ( ! $this->is_non_empty_string_or_stringable( $html ) ) {
if ( \is_int( $html ) || \is_float( $html ) ) {
// Replace all new lines with spaces.
$html = \preg_replace( '/(\r|\n)/', ' ', $html );
// Replace <br> tags with spaces.
$html = \preg_replace( '/<br(\s*)?\/?>/i', ' ', $html );
// Replace closing </p> and other tags with the same tag with a space after it, so we don't end up connecting words when we remove them later.
$html = \preg_replace( '/<\/(p|div|h\d)>/i', '</$1> ', $html );
// Replace list items with list identifiers so it still looks natural.
$html = \preg_replace( '/(<li[^>]*>)/i', '$1• ', $html );
$html = \wp_strip_all_tags( $html );
// Replace multiple spaces with one space.
$html = \preg_replace( '!\s+!', ' ', $html );
* Verifies that the received input is either a string or stringable object.
* @param string $html The original HTML.
private function is_non_empty_string_or_stringable( $html ) {
return ( \is_string( $html ) || ( \is_object( $html ) && \method_exists( $html, '__toString' ) ) ) && ! empty( $html );