otpauth/src/utils/pad.js

One Time Password (HOTP/TOTP) library for Node.js, Deno and browsers

/**
 * Pads a number with leading zeros.
 * @param {number|string} num Number.
 * @param {number} digits Digits.
 * @returns {string} Padded number.
 */
const pad = (num, digits) => {
	let prefix = '';
	let repeat = digits - String(num).length;
	while (repeat-- > 0) prefix += '0';
	return `${prefix}${num}`;
};

export { pad };