Is 'console.time' in nodejs synchronous or async?

Question

I am trying to log time for something. The general code looks like so:

var stream = db.call.stream();
stream.on('data', function () {
    if (first) {
        console.time('doSomething');
    }
    stream.pause();
    doSomethingWithData(data);
    if (stopCondition) {
        console.timeEnd('doSomething');
        done();
    } else {
        stream.resume();
    }
});

I would like to know if the call to console.time is blocking or asynchronous? I could not find this in the docs.

Answer 1

According to the source code of console.time and console.timeEnd,

Console.prototype.time = function(label) {
  this._times[label] = Date.now();
};


Console.prototype.timeEnd = function(label) {
  var time = this._times[label];
  if (!time) {
    throw new Error('No such label: ' + label);
  }
  var duration = Date.now() - time;
  this.log('%s: %dms', label, duration);
};

They just store the starting time against the label and calculate the time elapsed since the label timed.

They don't do anything asynchronously.

Note: In node.js, if a function is asynchronous, it will accept callback as one of the parameters.