44 lines
1.5 KiB
JavaScript
44 lines
1.5 KiB
JavaScript
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/**
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* Copyright 2020 Google LLC
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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// @license © 2020 Google LLC. Licensed under the Apache License, Version 2.0.
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/**
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* Returns whether the File System Access API is supported and usable in the
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* current context (for example cross-origin iframes).
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* @returns {boolean} Returns `true` if the File System Access API is supported and usable, else returns `false`.
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*/
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const supported = (() => {
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// ToDo: Remove this check once Permissions Policy integration
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// has happened, tracked in
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// https://github.com/WICG/file-system-access/issues/245.
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if ('top' in self && self !== top) {
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try {
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// This will succeed on same-origin iframes,
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// but fail on cross-origin iframes.
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top.location + '';
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} catch {
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return false;
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}
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} else if ('chooseFileSystemEntries' in self) {
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return 'chooseFileSystemEntries';
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} else if ('showOpenFilePicker' in self) {
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return 'showOpenFilePicker';
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}
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return false;
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})();
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export default supported;
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