locutus/powershell/string/padleft.js

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

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.padleft = padleft;
function padleft(str, totalWidth, paddingChar) {
    //      discuss at: https://locutus.io/powershell/padleft/
    // parity verified: PowerShell 7.4
    //     original by: Kevin van Zonneveld (https://kvz.io)
    //       example 1: padleft('42', 5)
    //       returns 1: '   42'
    //       example 2: padleft('42', 5, '0')
    //       returns 2: '00042'
    //       example 3: padleft('hello', 3)
    //       returns 3: 'hello'
    const source = String(str);
    const width = Math.trunc(Number(totalWidth));
    if (!Number.isFinite(width) || width < 0) {
        throw new RangeError('padleft(): totalWidth must be a non-negative integer');
    }
    const fill = paddingChar === undefined ? ' ' : String(paddingChar);
    if (fill === '') {
        return source;
    }
    return source.padStart(width, fill[0] ?? ' ');
}