should remove part of memory leaks

[arestov]

memory leaks through closures of callback in event listeners in foreight objects.

destroy should unsubscribe current object from any events in foreight objects

[arestov]

also self.swarm.listen( here can be problem

[rom1504]

I think it would be interesting to have some way to measure how much the memory leaks decreased.

[arestov]

You can use this trick.
#712 (comment)

Add this in every file and Class (instances of which could be destroyed) in every webtorrent module.
That run webtorrent for few hours. Or just add 10 torrent and then remove them all.
Take snapshot and you will see how many objects should be GCed by counting of MemoryLeak (filter by name)

var MemoryLeak = function(){}


Item.die = function() {
  // ...
  this.leak = new MemoryLeak()
  // ...
}

I guess it can be added in master branch with process.NODE_ENV == 'DEBUG'

var isDebugging = process.NODE_ENV == 'DEBUG';

//...

Item.die = function() {
  // ...
  if (isDebugging) {
    this.leak = new MemoryLeak()
  }
  // ...
}

(If your code has no leaks than GC will remove whole item, but if not — you will see MemoryLeak in memory profiler (snapshot))

[arestov]

Well, I've put MemoryLeak in some of files

Started webtorrent-desktop (whithout code in commit) download and got some leaks

Click start/stop and got more leaks

So looks like this commit 44e486b is not enough

I guess that this code is also problem:
https://github.com/feross/torrent-discovery/blob/master/index.js#L76
https://github.com/feross/torrent-discovery/blob/master/index.js#L58