43 lines
980 B
JavaScript
43 lines
980 B
JavaScript
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/**
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* Copyright (c) 2013-present, Facebook, Inc.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*
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*
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*/
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'use strict';
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/* eslint-disable fb-www/typeof-undefined */
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/* eslint-disable no-unused-vars */
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var invariant = require('./invariant');
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/**
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* Checks if a value is empty.
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*/
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function isEmpty(value) {
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if (Array.isArray(value)) {
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return value.length === 0;
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} else if (typeof value === 'object') {
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if (value) {
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!(!isIterable(value) || value.size === undefined) ? process.env.NODE_ENV !== 'production' ? invariant(false, 'isEmpty() does not support iterable collections.') : invariant(false) : void 0;
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for (var _ in value) {
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return false;
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}
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}
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return true;
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} else {
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return !value;
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}
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}
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function isIterable(value) {
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if (typeof Symbol === 'undefined') {
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return false;
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}
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return value[Symbol.iterator];
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}
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module.exports = isEmpty;
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