Would it be better to return the file extension with a period?

[7anshuai]

From Wikipedia:

A filename extension, file name extension or file extension is a suffix to the name of a computer file (e.g., .txt, .docx, .md).

When the ext without a period(.), i need write code like this:

import path from 'path';
import {fileTypeFromFile} from 'file-type';

const filetype =  await fileTypeFromFile('Unicorn.png'));
// {ext: 'png', mime: 'image/png'}

const pathname = path.format({ dir: '/path/to/somewhere', name: 'Unicorn', ext: filetype?.ext ? '.' + filetype?.txt : '' });
// /path/to/somewhere/Unicorn.png

With a period(.):

const filetype =  await fileTypeFromFile('Unicorn.png'));
// {ext: '.png', mime: 'image/png'}

const pathname = path.format({ dir: '/path/to/somewhere', name: 'Unicorn', ext: filetype?.ext });
// /path/to/somewhere/Unicorn.png

If the ext has a period, it's convenient to use it.

[sindresorhus]

The extension is png. The dot is just the separator. Same as the filename is not /Unicorn.png, since / is the path separator.

nodejs/node#44343