Document best practices: console.log

[mjhea0]

Thoughts on adding a few best practices around garbage collection. Adding a console.log for instance...

describe.only('test()', () => {
  it('does not leak when doing stuff', () => {
    iterate(6, () => { const test = new Person(); console.log(test); });
  });
});

function Person() {
  this.age = 1;
  this.name = 'mike';
}

vs

describe.only('test()', () => {
  it('does not leak when doing stuff', () => {
    iterate(6, () => { const test = new Person();  });
  });
});

function Person() {
  this.age = 1;
  this.name = 'mike';
}

[andywer]

Hey @mjhea0.

Adding "best practices" to the documentation is a good point! Concerning your example above... I haven't yet tried the code, but the console.log(test) should not introduce a leak or does it?

[mjhea0]

it prevents garbage collection. i don't think you can consider it a leak, but it does throw an error

[andywer]

I don't quite get why, though, to be honest. Why should console.log() keep a reference to the object after printing it? 🤔

But good to know. Thanks! Any other best practice proposals? 😉

[mjhea0]

http://stackoverflow.com/a/28859493/1799408

I imagine the same thing happens in node since it uses v8.

[andywer]

Thanks for the link!

Even an explicit delete test after console.log(test) does not seem to help... (My bad. delete does not mark the object for GC in JS at all; it's really just for removing props from an object)

[mjhea0]

firefox does the same. must be v8 and spidermonkey just keeping a reference for debugging purposes. another reason to git rid of those nasty console.logs!

[mjhea0]

Probably a good idea to add in the docs that leakage tests should be kept separate from your normal test suite. They took like triple amount of the time to run!

[andywer]

Good point! Got to open another issue and make a list...

[andywer]

Closing this as there is now #19. Let's collect ideas there :)