ilib-common/src/Path.js

Common utility functions for ilib. iLib is a cross-engine library of internationalization (i18n) classes written in pure JS

/*
 * Path.js - minimal pure js implementation of the nodejs path module
 * which can be used in web browsers as well
 *
 * Copyright © 2015, 2021-2022 JEDLSoft
 *
 * 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.
 */

/**
 * @module Path
 */

export default class Path {
    constructor() {}

    static fileUriToPath(uri) {
        if (typeof uri !== 'string' || uri.length <= 6 || !uri.startsWith('file:')) {
            throw new TypeError(
                'must pass in a file:// URI to convert to a file path'
            );
        }

        const re = /^(([^:\/?#]+):)?(\/\/([^\/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?/;
        const match = re.exec(uri);

        return match ? match[5] : '';
    }
}

/**
 * Return the parent directory of the given pathname
 * similar to the dirname shell function.
 * @static
 * @param {string} pathname path to check
 * @return {string} the parent dir of the given pathname
 */
Path.dirname = function(pathname) {
    if (!pathname) return pathname;
    pathname = Path.normalize(pathname);
    return (pathname === ".") ? ".." : Path.normalize(pathname + "/..");
};

/**
 * Return the normalized version of the given pathname. This
 * cleans up things like double directory separators and such.
 * @static
 * @param {string} pathname path to check
 * @return {string} the normalized version of the given pathname
 */
Path.normalize = function(pathname) {
    if (pathname) {
        pathname = pathname.replace(/\\/g, "/");
        pathname = pathname.replace(/\/\//g, "/");
        pathname = pathname.replace(/\/\//g, "/");
        pathname = pathname.replace(/\/[^/]*[^\./]\/\.\./g, "/.");
        pathname = pathname.replace(/^[^/]*[^\./]\/\.\./g, ".");
        pathname = pathname.replace(/\/\.\//g, "/");
        pathname = pathname.replace(/^\.\//, "");
        pathname = pathname.replace(/\/\//g, "/");
        pathname = pathname.replace(/\/\.$/, "");
        pathname = pathname.replace(/\/\//g, "/");
        if (pathname.length > 1) pathname = pathname.replace(/\/$/, "");
        if (pathname.length === 0) pathname = '.';
    }
    return pathname;
};

/**
 * Return a path that is the concatenation of all the of the arguments
 * which each name a path segment.
 * @static
 * @param {...string} var_args
 * @return {string} the concatenated pathname
 */
Path.join = function(var_args) {
    var arr = [];
    for (var i = 0; i < arguments.length; i++) {
        arr.push(arguments[i] && arguments[i].length > 0 ? arguments[i] : ".");
    }
    return Path.normalize(arr.join("/"));
};

/**
 * Return the base file name of the path. If the extension is given,
 * with or without the leading dot, then the extension is removed from
 * the base name.
 * @param {string} pathname the path to take the base name of
 * @param {string|undefined} extension the optional extension to remove
 * @return {string} the base name of the file without the extension
 */
Path.basename = function(pathname, extension) {
    var base = pathname;
    var slash = pathname.lastIndexOf("/");
    if (slash !== -1) {
        base = pathname.substring(slash+1);
    }

    if (extension) {
        var ext = extension[0] === "." ? extension : "." + extension;
        var index = base.lastIndexOf(ext);
        if (index > -1) {
            base = base.substring(0, index);
        }
    }

    return base;
};