Throw error when reusing keyPair for listens

[HDegroote]

No description provided.

[HDegroote]

I don't think this is needed, but left it in to sanity check.

(If it is needed, then we need to try-finally await this.dht.bind(), because that can throw too. Or alternatively, do this.dht.listening.add(this) after this check)

[mafintosh]

are we not deleting elsewhere?

[HDegroote]

We delete when server._gc is called (when server.close(), or when await this._announcer.start() errors).

But if there's an error while calling server.listen(), the server will remain in this.dht.listening, unless the user explicitly closes it.

The current approach is definitely bad. I think we either leave it to the user (as when `await this.dht.bind rejects) or pass through gc, as when the announcer errors (

hyperdht/lib/server.js

Lines 171 to 177 in b5cd15a

	try {
	await this._announcer.start()
	} catch (err) {
	await this._stopListening()
	this._gc()
	throw err
	}

)

The cleanest might be to wrap everything from await this.dht.bind() up to await this._announcer.start() in the try-finally

[mafintosh]

Thats a feature atm. The user owns the server until they call close on it, ever or not listen fails.

[HDegroote]

Aha, in that case I'll simply remove the delete and it should be good

[HDegroote]

I had misunderstood. I pushed a commit to modify the behaviour so it always cleans up if _listen throws before announcer.start() completes