Function tracking for console debugging

trackFn.js

/**
 * Track a function attached to an object.
 * For example to track: myObject.myFunc()
 *  trackFn(myObject, 'myFunc');
 * 
 * You can also track multiple functions at once:
 *  trackFn(myObject, ['myFunc1','myFunc2','myFunc3']);
 *
 * optionally set st=true to get a stack trace
 * optionally you can supply a msg argument
 */
window.trackFnThis = {};
function trackFn(obj, prop, st, msg) {
  if (Array.isArray(prop)) {
    prop.forEach(function(v) { trackFn(obj,v,st,msg); });
    return;
  }
  var fn = obj[prop];
  var m = (msg||'')+(msg?'.':'')+prop;
  if (fn.__trackingFn__) { console.log("("+m+": We were already tracking this, updating the tracker.)"); fn = fn.__trackingFn__; }
  tFn = function() {
    window.trackFnThis[m] = this;
    console.log.apply(console,['(trackFn)',m+':'].concat(arguments));
    if (st) console.log((new Error).stack.match(/^.+$/mg).slice(2).join("\n"));
    return fn.apply(obj, arguments);
  };
  tFn.__trackingFn__ = fn;
  obj[prop] = tFn;
}

/**
 * Performs deep traverse through object and
 * tracks all functions it finds along the way
 */
function trackObjectFns(obj, st, msg, objs) {
  objs = objs || [];
  if (objs.indexOf(obj) != -1) return; // prevent infinite recursion
  objs.push(obj);
  try {
    for (p in obj) {
      var m = [msg||'',p].join('.');
      if (typeof obj[p] == 'object') {
          trackObjectFns(obj[p],st, m, objs);
      }
      if (typeof obj[p] == 'function') {
          trackFn(obj, p, st, m);
      }
    }
  } catch (e) {
    console.warn('(trackObjectFns) Failed to traverse an object ',e)
  }
}