Process ends in case of deferred promise is used

[Mindaugas Juskevicius]

Having issue where in case of deferred promise used in repeat loop, program completely exists everything. After handling single connection, I would expect it to go back to while loop, waiting for new connection, but instead it exists handleConnection and afterwards the while loop. No exception, no errors. Only happens if deferred is used.

Loop::run(function () use ($host) {
    $server = Server::listen($host, (new BindContext())->withTcpNoDelay());
    
    while ($socket = yield $server->accept()) {
        $this->handleConnection($socket);
    }
}

private function handleConnection(ResourceSocket $socket): void
{
        $counter = 0;
        $deferred = new Deferred();
        
        Loop::repeat(100, function ($watcherId) use (&$counter, $deferred) {
            if($counter === 3) {
                $deferred->resolve();
                Loop::cancel($watcherId);

            }
            $counter++;
        });

        wait($deferred->promise());
        
        return;
}

[Niklas Keller]

Hey @Mindaho,

the issue here is using wait inside a running event loop, which will call Loop::stop() internally and exit all nested event loop runs.

It's best to use Amp\call and a generator there and return a Promise from handleConnection as well.

This will be much nicer in v2, where you can just await everything synchronously everywhere.