JavaScript Cookie Trapper

trapper.js

// Use to detect calls to document.cookie="xxx"
(function (){
    var s = document.__lookupSetter__('cookie').bind(document),
        g = document.__lookupGetter__('cookie').bind(document);
    
    Object.defineProperty(document, 'cookie', {
        get() {
            return g();
        },
        set(n) {
            console.error('Setting cookie:', n);
            s(n);
        }
    });
})();