deblan.io-murph/assets/js/addons/form.js

const $ = require('jquery');

module.exports = function() {
    $('.custom-file-input').on('change', function(event) {
        let inputFile = event.currentTarget;

        $(inputFile).parent()
            .find('.custom-file-label')
            .html(inputFile.files[0].name);
    });
};