function componentWillUpdate()

in index.js [27:42]


function componentWillUpdate(nextProps, nextState) {
  try {
    var prevProps = this.props;
    var prevState = this.state;
    this.props = nextProps;
    this.state = nextState;
    this.__reactInternalSnapshotFlag = true;
    this.__reactInternalSnapshot = this.getSnapshotBeforeUpdate(
      prevProps,
      prevState
    );
  } finally {
    this.props = prevProps;
    this.state = prevState;
  }
}