do_shortcode()

do_shortcode( string $content, bool $ignore_html = false ): string

function do_shortcode( $content, $ignore_html = false ) {
	global $shortcode_tags;

	if ( ! str_contains( $content, '[' ) ) {
		return $content;
	}

	if ( empty( $shortcode_tags ) || ! is_array( $shortcode_tags ) ) {
		return $content;
	}

	// Find all registered tag names in $content.
	preg_match_all( '@\[([^<>&/\[\]\x00-\x20=]++)@', $content, $matches );
	$tagnames = array_intersect( array_keys( $shortcode_tags ), $matches[1] );

	if ( empty( $tagnames ) ) {
		return $content;
	}

	// Ensure this context is only added once if shortcodes are nested.
	$has_filter   = has_filter( 'wp_get_attachment_image_context', '_filter_do_shortcode_context' );
	$filter_added = false;

	if ( ! $has_filter ) {
		$filter_added = add_filter( 'wp_get_attachment_image_context', '_filter_do_shortcode_context' );
	}

	$content = do_shortcodes_in_html_tags( $content, $ignore_html, $tagnames );

	$pattern = get_shortcode_regex( $tagnames );
	$content = preg_replace_callback( "/$pattern/", 'do_shortcode_tag', $content );

	// Always restore square braces so we don't break things like <!--[if IE ]>.
	$content = unescape_invalid_shortcodes( $content );

	// Only remove the filter if it was added in this scope.
	if ( $filter_added ) {
		remove_filter( 'wp_get_attachment_image_context', '_filter_do_shortcode_context' );
	}

	return $content;
}