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/**
* 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';
/**
* Given a `prevElement` and `nextElement`, determines if the existing
* instance should be updated as opposed to being destroyed or replaced by a new
* instance. Both arguments are elements. This ensures that this logic can
* operate on stateless trees without any backing instance.
*
* @param {?object} prevElement
* @param {?object} nextElement
* @return {boolean} True if the existing instance should be updated.
* @protected
*/
function shouldUpdateReactComponent(prevElement, nextElement) {
var prevEmpty = prevElement === null || prevElement === false;
var nextEmpty = nextElement === null || nextElement === false;
if (prevEmpty || nextEmpty) {
return prevEmpty === nextEmpty;
}
var prevType = typeof prevElement;
var nextType = typeof nextElement;
if (prevType === 'string' || prevType === 'number') {
return nextType === 'string' || nextType === 'number';
} else {
return nextType === 'object' && prevElement.type === nextElement.type && prevElement.key === nextElement.key;
}
}
module.exports = shouldUpdateReactComponent;
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