Prestashop – Error showing php "defien(..) code when entering the website

I have a Prestashop website and my Hosting has done some update that allow me to chose php version from the DirectAdmin panel,

but now after the change when I enter the website I see some php line of code with “define…” but all the rest is working fine in the website.

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What can cause it? and How can I hide those line of code for the user?

Source: stackoverflow-php

Increasing and decreasing the quantity of products in Prestashop

I want to add increasing and decreasing of quantity in my product list. This is my code in Prestashop 1.6:

 // The button to increment the product value
$(document).on('click', '.product_quantity_up', function(e){
        fieldName = $(this).data('field-qty');
        var currentVal = parseInt($('input[name='+fieldName+']').val());
        if (!allowBuyWhenOutOfStock && quantityAvailable > 0)
                quantityAvailableT = quantityAvailable;
                quantityAvailableT = 100000000;
        if (!isNaN(currentVal) && currentVal  1)
                $('input[name='+fieldName+']').val(currentVal - 1).trigger('keyup');


Like You see I have js and input filed called quantity_wanted. When I press + or – nothing happened. This is a source code. If You want see the website check the link:

Many thanks for help.
Kind regards

Source: stackoverflow-javascript