ws-receive: return #f for a still-CONNECTING browser socket, not 'closed

Message

On WASM the browser WebSocket opens asynchronously, so ws-connected? is #f during the CONNECTING window as well as after CLOSE (ws-connect sets state 'open optimistically; the raw socket reaches readyState OPEN later). ws-receive reported both as 'closed, and irc-ws-receive latched the session dead on the first poll that landed before the socket finished opening -- fatal on higher-latency links (phone/VPN ~455ms open) though never hit on localhost (~31ms). Consult the new wasm-websocket-connecting? (readyState) so a connecting socket returns #f ("no data yet") and only a genuine close returns 'closed. Native path unchanged (guarded by cond-expand).

Changed

 src/sigil/websocket/connection.sgl | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

Diff

src/sigil/websocket/connection.sglmodified

@@ -528,7 +528,22 @@

528

(define (ws-receive conn)

529

(: ws-connection? -> any?)

530

(if (not (ws-connected? conn))

−531

'closed

+531

(cond-expand

+532

(wasm

+533

;; The browser WebSocket opens ASYNChronously, so ws-connected?

+534

;; is #f during the CONNECTING window as well as after CLOSE

+535

;; (ws-connect sets state 'open optimistically; the raw socket

+536

;; reaches readyState OPEN later). Consult the readyState to tell

+537

;; them apart: a still-connecting socket returns #f ("no data

+538

;; yet"), only a genuinely closed socket returns 'closed. Without

+539

;; this, the first poll that lands before the socket finishes

+540

;; opening reports 'closed and latches the session dead — the

+541

;; browser slow-open bug (never hit on localhost's ~31ms open,

+542

;; fatal over phone/VPN's ~455ms).

+543

(if (wasm-websocket-connecting? (ws-connection-socket conn))

+544

#f

+545

'closed))

+546

(else 'closed))

547

(cond-expand

548

(wasm

549

(let ((result (process-wasm-event