45 lines
1.2 KiB
JavaScript
45 lines
1.2 KiB
JavaScript
/**
|
|
* 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 invariant = require('fbjs/lib/invariant');
|
|
|
|
/**
|
|
* Accumulates items that must not be null or undefined.
|
|
*
|
|
* This is used to conserve memory by avoiding array allocations.
|
|
*
|
|
* @return {*|array<*>} An accumulation of items.
|
|
*/
|
|
function accumulate(current, next) {
|
|
!(next != null) ? process.env.NODE_ENV !== 'production' ? invariant(false, 'accumulate(...): Accumulated items must be not be null or undefined.') : _prodInvariant('29') : void 0;
|
|
|
|
if (current == null) {
|
|
return next;
|
|
}
|
|
|
|
// Both are not empty. Warning: Never call x.concat(y) when you are not
|
|
// certain that x is an Array (x could be a string with concat method).
|
|
if (Array.isArray(current)) {
|
|
return current.concat(next);
|
|
}
|
|
|
|
if (Array.isArray(next)) {
|
|
return [current].concat(next);
|
|
}
|
|
|
|
return [current, next];
|
|
}
|
|
|
|
module.exports = accumulate; |