function RichText(node) {
    _classCallCheck(this, RichText);

    this._node = [];
    this._cell = null;
    this._remainingNodes = [];

    if (node) {
      for (var i = 0; i < node.length; i++) {
        var fragment = node[i];

        if (fragment.name === 'r') {
          this._node.push(new RichTextFragment(fragment, null, this));
        } else {
          // special node, e.g. rPh, phoneticPr in Japanese language.
          this._remainingNodes.push(fragment);
        }
      }
    }
  }
Creates a new instance of RichText. If you get the instance by calling `Cell.value()`,
adding a text contains line separator will trigger {@link Cell.style}('wrapText', true), which
will make MS Excel show the new line. i.e. In MS Excel, Tap "alt+Enter" in a cell, the cell
will set wrap text to true automatically.

@param {undefined|null|Object} [node] - The node stored in the shared string