fix: retry on first connection failure and on failed IRC registration

[mbologna]

Problem

When an IRC connection fails for the first time (DNS not yet ready, transient network error, ECONNRESET during registration), The Lounge shows:

Disconnected from the network, and will not reconnect. Use /connect to reconnect again.

Even though auto_reconnect is enabled and auto_reconnect_max_retries is set to a high value (e.g. 30 in The Lounge). This has been reported in several places:

• ECONNRESET without any retries after thelounge/thelounge#4103 — ECONNRESET with no retries
• TL stops reconnecting on some errors while it should continue to reconnect. thelounge/thelounge#3419 — stops reconnecting after registration errors
• This issue (On some irc-errors reconnecting shouldn't stop. #211) — original root cause discussion

Root cause

The reconnect decision in socketClose is:

} else if (that.reconnect_attempts && that.reconnect_attempts < that.auto_reconnect_max_retries) {
    should_reconnect = true;

// If we were originally connected OK, reconnect
} else if (was_connected && safely_registered) {
    should_reconnect = true;
} else {
    should_reconnect = false;
}

Bug 1 — initial value: reconnect_attempts is initialised to 0. Since 0 is falsy in JavaScript, the first branch never fires on a first-ever connection failure. was_connected is also false, so the second branch doesn't fire either. Result: the very first failure gives up immediately, no matter how high max_retries is.

Bug 2 — premature reset: reconnect_attempts is reset to 0 inside socketOpen (raw TCP connect). This means a connection that reached the TCP layer but failed IRC registration (auth timeout, server-side ECONNRESET during NICK/USER, netsplit during connect) will reset the counter on the next attempt's TCP connect, effectively giving only one IRC-level retry before exhausting the counter.

Both bugs can be observed in the log pattern from #4103:

Reconnecting in 11 seconds… (Attempt 4)   ← TCP connects
Connected to the network.                  ← socketOpen fires, resets counter to 0
-server- *** Found your hostname
Connection closed unexpectedly: ECONNRESET ← socketClose fires, reconnect_attempts == 0 → give up
Disconnected from the network, and will not reconnect.

Fix

Three minimal changes, first proposed by @mornfall in this issue:

1. Initialise reconnect_attempts to 1 — the first failure now satisfies reconnect_attempts > 0 && reconnect_attempts < max_retries, triggering a retry.

2. Remove the reset from socketOpen — a raw TCP connection is not a successful IRC session. The counter should not reset until IRC registration completes.

3. Reset to 1 in registeredSuccessfully — after a fully successful registration, the counter resets so the next connection problem gets a fresh set of retries.

Validation

@mornfall has been running this exact fix in production for 2+ years with ~100 users without issues (last comment in this thread). The fix has also been independently validated by @tokariu.

Diff

-        this.reconnect_attempts = 0;
+        this.reconnect_attempts = 1;

     registeredSuccessfully() {
         this.registered = Date.now();
+        this.reconnect_attempts = 1;
     }

     function socketOpen() {
         that.debugOut('Socket fully connected');
-        that.reconnect_attempts = 0;
         that.connected = true;

[tokariu]

I've been running this fix on my instance for years now without issues and the handling of reconnects is much better this way. it's like it should've been from the beginning. so let's add it then.