Wrong Class Name Showing in console.log

Question

In Node.js, I've created a class in which I'm logging instances of that class to the console during tests.

When I console.log(anObjectFromThatClass), the letters "Vo" precede the opening curly brackets of that object in the terminal's output.

Normally, I'd expect to see the class name preceding the curly brackets, but instead I see Vo {} . The actually class name does not have a "V" or an "o" anywhere in its name, nor does it extend another class having a "V" or "o" in its name.

I tried googling to see what "Vo" means, but couldn't find anything due to all the false positives of that search.

Due to policy, I can't post the actual class here. I realize I'm not giving you much to go on, but can you think of a reason why "Vo" would precede the curly brackets when console logging an instance of a class not containing 'Vo' in its name? Does it have something to do with some type of live view provided by the V8 engine to node.js?

I've tried to create a class that reproduces this behavior, for this post, but every class I create, simply logs the correct class name before the curly brackets. This code has a lot of promises and async await stuff going on, perhaps that can alter class-names outputted by console.log?

I should probably just be glad this code is working good and forget about the idiosyncrasies of console.log() . However, I remain very curious, so please tell me if you know what this 'Vo' means.

Answer 1

The letters that come before the logged object when it gets console.log ged will be the name of the class, as it's represented in the code that was run . It sounds like the code that gets run is different from your source code - perhaps it's minified in some way, resulting in the run code having a class Vo { or something of the sort, even if the source code uses class MyClass { .

If the code is run without minification or other transpilation, you'll see MyClass { instead of Vo { when the object gets logged.