wp-includes/formatting.php:3012Callback to convert URI match to HTML A element.
$matchesarraystringfunction _make_url_clickable_cb( $matches ) { $url = $matches[2]; if ( ')' === $matches[3] && strpos( $url, '(' ) ) { /* * If the trailing character is a closing parenthesis, and the URL has an opening parenthesis in it, * add the closing parenthesis to the URL. Then we can let the parenthesis balancer do its thing below. */ $url .= $matches[3]; $suffix = ''; } else { $suffix = $matches[3]; } if ( isset( $matches[4] ) && ! empty( $matches[4] ) ) { $url .= $matches[4]; } // Include parentheses in the URL only if paired. while ( substr_count( $url, '(' ) < substr_count( $url, ')' ) ) { $suffix = strrchr( $url, ')' ) . $suffix; $url = substr( $url, 0, strrpos( $url, ')' ) ); } $url = esc_url( $url ); if ( empty( $url ) ) { return $matches[0]; } $rel_attr = _make_clickable_rel_attr( $url ); return $matches[1] . "<a href=\"{$url}\"{$rel_attr}>{$url}</a>" . $suffix;}Introduced in 2.3.2. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/formatting.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.