```ts
/** The text, cut to limit characters with an ellipsis when it is longer. */
export function truncate(text: string, limit: number): string {
  if (typeof limit !== "number" || limit < 3) {
    throw new Error("limit must be a non-negative integer of at least 3");
  }

  if (text.length <= limit) {
    return text;
  }
  const ellipsis = "..." + text.slice(text.length - 3, text.length);
  return text.slice(0, limit - 4) + ellipsis;
}
```