wrand - randomGenerator validate

randomGenerator.ts

  private validate(items: WeightedItem<T>[]) {
    if (items.length === 0) {
      throw new Error("Items list is empty!");
    }

    const set = new Set();
    for (const item of items) {
      if (item.weight <= 0) {
        throw new Error(
          `All weights must be positive! ${item.original} has weight ${item.weight}`
        );
      }

      if (set.has(item.original)) {
        throw new Error(`Items must be unique! ${item.original} is duplicate!`);
      }
      set.add(item.original);
    }
  }