/** * @license Apache-2.0 * * Copyright (c) 2021 The Stdlib Authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ 'use strict'; // MODULES // var resolve = require( 'path' ).resolve; var isString = require( '@stdlib/assert/is-string' ).isPrimitive; var isFunction = require( '@stdlib/assert/is-function' ); var cwd = require( '@stdlib/process/cwd' ); var exists = require( './../../exists' ); var validate = require( './validate.js' ); // MAIN // /** * Asynchronously resolves a path according to a predicate function by walking parent directories. * * @param {string} path - path to resolve * @param {Options} [options] - function options * @param {string} [options.dir] - base directory * @param {Function} predicate - callback which tests whether a resolved path passes a test * @param {Function} clbk - callback to invoke after resolving a path * @throws {TypeError} first argument must be a string * @throws {TypeError} predicate function argument must be a function * @throws {TypeError} callback argument must be a function * @throws {TypeError} options argument must be an object * @throws {TypeError} must provide valid options * * @example * resolveParentPathBy( 'package.json', predicate, onPath ); * * function predicate( path, next ) { * next( null, true ); * } * * function onPath( error, path ) { * if ( error ) { * throw error; * } * console.log( path ); * } */ function resolveParentPathBy( path, options, predicate, clbk ) { var spath; var child; var test; var opts; var done; var dir; var err; if ( !isString( path ) ) { throw new TypeError( 'invalid argument. First argument must be a string primitive. Value: `' + path + '`.' ); } opts = {}; if ( arguments.length > 3 ) { err = validate( opts, options ); if ( err ) { throw err; } test = predicate; done = clbk; } else { test = options; done = predicate; } if ( !isFunction( test ) ) { throw new TypeError( 'invalid argument. Predicate function argument must be a function. Value: `' + test + '`.' ); } if ( !isFunction( done ) ) { throw new TypeError( 'invalid argument. Callback argument must be a function. Value: `' + done + '`.' ); } if ( opts.dir ) { dir = resolve( cwd(), opts.dir ); } else { dir = cwd(); } spath = resolve( dir, path ); exists( spath, onExists ); /** * Resolves the next candidate path. * * @private * @returns {void} */ function next() { // Resolve a parent directory: child = dir; dir = resolve( dir, '..' ); // If we have already reached root, we cannot resolve any higher directories... if ( child === dir ) { return done( null, null ); } // Resolve the next search path: spath = resolve( dir, path ); exists( spath, onExists ); } /** * Callback invoked after checking for path existence. * * @private * @param {(Error|null)} error - error object * @param {boolean} bool - boolean indicating if a path exists * @returns {void} */ function onExists( error, bool ) { // eslint-disable-line handle-callback-err if ( bool ) { return test( spath, onTest ); } next(); } /** * Callback invoked after testing a resolved path. * * @private * @param {(Error|null)} error - error object * @param {boolean} bool - boolean indicating if a path exists * @returns {void} */ function onTest( error, bool ) { if ( error ) { return done( error ); } if ( bool ) { return done( null, spath ); } next(); } } // EXPORTS // module.exports = resolveParentPathBy;