_sinkDown()

in packages/fbjs/src/struct/Heap.js [115:149]

• 29 lines of code
• 9 McCabe index (conditional complexity)

  _sinkDown(index) {
    const elt = this._items[index];

    while (true) {
      const leftChildIndex = 2 * (index + 1) - 1;
      const rightChildIndex = 2 * (index + 1);
      let swapIndex = -1;

      if (leftChildIndex < this._size) {
        const leftChild = this._items[leftChildIndex];
        if (this._comparator(leftChild, elt)) {
          swapIndex = leftChildIndex;
        }
      }

      if (rightChildIndex < this._size) {
        const rightChild = this._items[rightChildIndex];
        if (this._comparator(rightChild, elt)) {
          if (swapIndex === -1 ||
              this._comparator(rightChild, this._items[swapIndex])) {
            swapIndex = rightChildIndex;
          }
        }
      }

      // if we don't have a swap, stop
      if (swapIndex === -1) {
        return;
      }

      this._items[index] = this._items[swapIndex];
      this._items[swapIndex] = elt;
      index = swapIndex;
    }
  }