Gulp 4 does nothing into certain folder name

[mvicens]

In a sample folder named "x", the Gulp file looks such simple like:

const { src, dest } = require('gulp');

exports.default = () => src('index.js').pipe(dest('dist/'));

Then, having also a index.js in the same folder, when you execute Gulp, it works fine: it creates a folder named "dist" with a JS file.

The point is that if the main folder is renamed to "[x]", executing Gulp, the terminal outputs the same (seeming to do the same thing) but nothing really occurs! And no error is launched.