locutus/esm/golang/url/JoinPath.js

Locutus other languages' standard libraries to JavaScript for fun and educational purposes

const cleanPath = (path) => {
    if (path === '') {
        return '.';
    }
    const rooted = path.startsWith('/');
    const segments = path.split('/');
    const stack = [];
    for (const segment of segments) {
        if (segment === '' || segment === '.') {
            continue;
        }
        if (segment === '..') {
            const top = stack.at(-1);
            if (top && top !== '..') {
                stack.pop();
            }
            else if (!rooted) {
                stack.push('..');
            }
            continue;
        }
        stack.push(segment);
    }
    const cleaned = `${rooted ? '/' : ''}${stack.join('/')}`;
    if (cleaned === '') {
        return rooted ? '/' : '.';
    }
    return cleaned;
};
const joinPathParts = (parts) => {
    if (parts.every((part) => part === '')) {
        return '';
    }
    return cleanPath(parts.join('/'));
};
export function JoinPath(base, ...elem) {
    //      discuss at: https://locutus.io/golang/url/JoinPath
    // parity verified: Go 1.23
    //     original by: Kevin van Zonneveld (https://kvz.io)
    //          note 1: Joins and cleans URL path elements while preserving query/fragment for absolute URLs.
    //       example 1: JoinPath('https://locutus.io/api/', 'v1', 'users')
    //       returns 1: 'https://locutus.io/api/v1/users'
    //       example 2: JoinPath('https://locutus.io/api/v1?x=1', '..', 'v2')
    //       returns 2: 'https://locutus.io/api/v2?x=1'
    //       example 3: JoinPath('/a/b/', '../c')
    //       returns 3: '/a/c'
    const baseValue = String(base);
    const parts = [baseValue, ...elem.map((part) => String(part))];
    try {
        const url = new URL(baseValue);
        const joinedPath = joinPathParts([url.pathname, ...elem.map((part) => String(part))]);
        url.pathname = joinedPath === '' ? '/' : joinedPath.startsWith('/') ? joinedPath : `/${joinedPath}`;
        return url.toString();
    }
    catch {
        return joinPathParts(parts);
    }
}