es-toolkit/dist/string/pad.js

A state-of-the-art, high-performance JavaScript utility library with a small bundle size and strong type annotations.

//#region src/string/pad.ts
/**
* Pads string on the left and right sides if it's shorter than length. Padding characters are truncated if they can't be evenly divided by length.
* If the length is less than or equal to the original string's length, or if the padding character is an empty string, the original string is returned unchanged.
*
* @param str - The string to pad.
* @param [length] - The length of the resulting string once padded.
* @param [chars] - The character(s) to use for padding.
* @returns The padded string, or the original string if padding is not required.
*
* @example
* const result1 = pad('abc', 8);         // result will be '  abc   '
* const result2 = pad('abc', 8, '_-');   // result will be '_-abc_-_'
* const result3 = pad('abc', 3);         // result will be 'abc'
* const result4 = pad('abc', 2);         // result will be 'abc'
*
*/
function pad(str, length, chars = " ") {
	return str.padStart(Math.floor((length - str.length) / 2) + str.length, chars).padEnd(length, chars);
}
//#endregion
exports.pad = pad;