debugging - How to debug javascript when it goes into infinite loops and recursive calls in Javascript?

Question

When you are in the infinite loop or recursive calls, basically the browser stops responding to anything (either on Chrome or FF). You cannot see logs, cannot get into debugger, even you cannot open the console itself. The browser just simply freezes. This is so annoying. It seems I can do nothing but sitting here scratching my head... Anyone can shed light on how to solve this?

Answer 1

Another trick you could try is to have the Web developer tools in Chrome open and try to hit Pause when the Browser apparently hangs. Then it should break at the line where it's currently executing. With some stepping out you should get to the bottom of this.

Assuming you know (or suspect) the function where the infite loop happens you could add code like this:

var calls = 0;
function iSuspectToBeLoopingInfititely() {
  calls += 1;
  if (calls > 100) { debugger; }
}

This will stop the JavaScript debugger in Chrome once the method has been called 100 times. Note: Chrome will only break for debugger; calls if you actually have the Developer Tools window open.