truncate method
Truncates the string to the specified length and adds an ellipsis if truncated.
@param length The maximum length of the returned string, not including the ellipsis. @param ellipsis The string to append if truncation occurs. Defaults to '...'. @return The truncated string with ellipsis if needed, or the original string if no truncation occurred.
Implementation
String truncate(int length, {String ellipsis = '...'}) {
if (this.length <= length) return this;
return '${substring(0, length)}$ellipsis';
}