86 lines
1.7 KiB
JavaScript
86 lines
1.7 KiB
JavaScript
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/**
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* @license Apache-2.0
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*
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* Copyright (c) 2018 The Stdlib Authors.
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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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'use strict';
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// MODULES //
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var fs = require( 'fs' );
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// FUNCTIONS //
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var fcn;
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if ( typeof fs.access === 'function' ) {
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fcn = fs.access;
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} else {
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fcn = fs.stat;
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}
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// MAIN //
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/**
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* Tests whether a path exists on the filesystem.
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*
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* @param {(string|Buffer)} path - path to test
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* @param {Function} clbk - callback to invoke after testing path existence
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*
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* @example
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* exists( __dirname, done );
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*
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* function done( error, bool ) {
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* if ( error ) {
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* console.error( error );
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* }
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* if ( bool ) {
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* console.log( '...path exists.' );
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* } else {
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* console.log( '...path does not exist.' );
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* }
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* }
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*/
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function exists( path, clbk ) {
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fcn( path, done );
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/**
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* Callback invoked upon performing a filesystem call.
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*
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* @private
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* @param {(Error|null)} error - error object
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* @returns {void}
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*/
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function done( error ) {
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if ( clbk.length === 2 ) {
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if ( error ) {
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return clbk( error, false );
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}
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return clbk( null, true );
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}
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if ( error ) {
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return clbk( false );
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}
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return clbk( true );
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}
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}
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// EXPORTS //
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module.exports = exists;
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