Detect if callback is called - async version

gistfile1.js

function doTest (callback, asyncTimeout) {
    var isCallbackCalled = false;
    var timedOut = false;
    var timer = null;

    var successCallback = function () {
        if (! timedOut) { // If code success but fail already reported, keep failed
            alert('Callback called');
            isCallbackCalled = true;
            if (asyncTimeout && timer) {
                clearTimeout(timer);
            }
        }
    };

    callback.apply(null, [ successCallback ]);
    
    if (asyncTimeout && ! isCallbackCalled) {
        timer = setTimeout(function() {
            alert('Callback not called!');
            timedOut = true;
        }, asyncTimeout);
    }
    else {
        if (! isCallbackCalled) {
            alert('Callback not called');
        }
    }
}

doTest(function (callback) {
    alert('Test 1, callback called!');
    setTimeout(callback, 100);
}, 200);
doTest(function(callback) {
    alert('Test 2, callback not called');
});