ant-design/components/tree/index.jsx

import React from 'react';
import RcTree from 'rc-tree';
import animation from '../_util/openAnimation';

export default class Tree extends React.Component {
  static TreeNode = RcTree.TreeNode;

  static defaultProps = {
    prefixCls: 'ant-tree',
    checkable: false,
    showIcon: false,
    openAnimation: animation,
  }

  render() {
    const props = this.props;
    let checkable = props.checkable;
    if (checkable) {
      checkable = <span className={`${props.prefixCls}-checkbox-inner`}></span>;
    }
    return (
      <RcTree {...props} checkable={checkable}>
        {this.props.children}
      </RcTree>
    );
  }
}