Async parseString hides exception

[mcheshkov]

var xml2js = require('xml2js');
xml2js.parseString("<a></a>", {async: true}, function(err, res){
    throw new Error("test");
});

This script does not show any unhandled errors.

[Leonidas-from-XIV]

This is due telling Node to call the processing function via setImmediate which calls it when the scheduler decides it's time, with no way to pass the exception back to the code that called parseString in the first place.

If you would like to get that exception, you could have an error handler either in the callback directly or call an error callback from a catch block in the callback.

[mcheshkov]

I don't want to catch exception, I want proper unhandled exception.

This script

setImmediate(function(){
    throw new Error("test");
});

Gives me this in terminal

$ node a && echo "Good" || echo "Bad"
/home/cheshkov/xlsx_temp/a.js:6
    throw new Error("test");
    ^

Error: test
    at Immediate._onImmediate (a.js:6:8)
    at processImmediate [as _immediateCallback] (timers.js:383:17)
Bad

But xml2js comsume this exception, and leave no trace

var xml2js = require('xml2js');
xml2js.parseString("<a></a>", {async: true}, function(err, res){
    throw new Error("test");
});

$ node a && echo "Good" || echo "Bad"
Good