blob: 527d6e64a392292ccbf061c6750b4095e8833f89 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
/**
* Copyright 2013-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
*/
'use strict';
var _prodInvariant = require('./reactProdInvariant');
var ReactElement = require('./ReactElement');
var invariant = require('fbjs/lib/invariant');
/**
* Returns the first child in a collection of children and verifies that there
* is only one child in the collection.
*
* See https://facebook.github.io/react/docs/top-level-api.html#react.children.only
*
* The current implementation of this function assumes that a single child gets
* passed without a wrapper, but the purpose of this helper function is to
* abstract away the particular structure of children.
*
* @param {?object} children Child collection structure.
* @return {ReactElement} The first and only `ReactElement` contained in the
* structure.
*/
function onlyChild(children) {
!ReactElement.isValidElement(children) ? process.env.NODE_ENV !== 'production' ? invariant(false, 'React.Children.only expected to receive a single React element child.') : _prodInvariant('143') : void 0;
return children;
}
module.exports = onlyChild;
|
