Fix race in wasm test

ci/wasm.sh

@@ -11,7 +11,7 @@ GOOS=js GOARCH=wasm golint -set_exit_status ./...
 
 wsjstestOut="$(mktemp)"
 go install ./internal/wsjstest
-timeout 30s wsjstest >> "$wsjstestOut" &
+timeout 30s wsjstest >> "$wsjstestOut" 2>&1 &
 wsjstestPID=$!
 
 # See https://superuser.com/a/900134
@@ -24,6 +24,7 @@ fi
 go install github.com/agnivade/wasmbrowsertest
 GOOS=js GOARCH=wasm go test -exec=wasmbrowsertest ./... -args "$WS_ECHO_SERVER_URL"
 
+kill "$wsjstestPID"
 if ! wait "$wsjstestPID"; then
   echo "--- wsjstest exited unsuccessfully"
   echo "output:"

internal/wsjstest/main.go

@@ -9,8 +9,9 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"os"
-	"runtime"
+	"os/signal"
 	"strings"
+	"syscall"
 
 	"nhooyr.io/websocket"
 	"nhooyr.io/websocket/internal/wsecho"
@@ -33,12 +34,13 @@ func main() {
 		if !errors.As(err, &ce) || ce.Code != websocket.StatusNormalClosure {
 			log.Fatalf("unexpected loop error: %+v", err)
 		}
-
-		os.Exit(0)
 	}))
 
 	wsURL := strings.Replace(s.URL, "http", "ws", 1)
 	fmt.Printf("%v\n", wsURL)
 
-	runtime.Goexit()
+	sigs := make(chan os.Signal)
+	signal.Notify(sigs, syscall.SIGTERM)
+
+	<-sigs
 }

websocket_js.go

@@ -35,6 +35,9 @@ type Conn struct {
 	readSignal chan struct{}
 	readBufMu  sync.Mutex
 	readBuf    []wsjs.MessageEvent
+
+	// Only used by tests
+	receivedCloseFrame chan struct{}
 }
 
 func (c *Conn) close(err error) {
@@ -55,7 +58,11 @@ func (c *Conn) init() {
 
 	c.isReadClosed = &atomicInt64{}
 
+	c.receivedCloseFrame = make(chan struct{})
+
 	c.releaseOnClose = c.ws.OnClose(func(e wsjs.CloseEvent) {
+		close(c.receivedCloseFrame)
+
 		cerr := CloseError{
 			Code:   StatusCode(e.Code),
 			Reason: e.Reason,

websocket_js_export_test.go

+// +build js
+
+package websocket
+
+import (
+	"context"
+	"fmt"
+)
+
+func (c *Conn) WaitCloseFrame(ctx context.Context) error {
+	select {
+	case <-c.receivedCloseFrame:
+		return nil
+	case <-ctx.Done():
+		return fmt.Errorf("failed to wait for close frame: %w", ctx.Err())
+	}
+}

websocket_js_test.go

@@ -50,4 +50,9 @@ func TestConn(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+
+	err = c.WaitCloseFrame(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
 }