34 lines
856 B
JavaScript
34 lines
856 B
JavaScript
/**
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* Copyright (c) Nicolas Gallagher.
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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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import { canUseDOM } from 'fbjs/lib/ExecutionEnvironment'; // $FlowFixMe: HTMLStyleElement is incorrectly typed - https://github.com/facebook/flow/issues/2696
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export default function createCSSStyleSheet(id) {
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if (canUseDOM) {
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var element = document.getElementById(id);
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if (element != null) {
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// $FlowFixMe: HTMLElement is incorrectly typed
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return element.sheet;
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} else {
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var _element = document.createElement('style');
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_element.setAttribute('id', id);
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var head = document.head;
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if (head) {
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head.insertBefore(_element, head.firstChild);
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}
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return _element.sheet;
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}
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} else {
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return null;
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}
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} |