fix: sync session membership routing fixes

internal/mtprotoedge/layer_seed_test.go

@@ -0,0 +1,73 @@
+package mtprotoedge
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"go.uber.org/zap/zaptest"
+
+	"github.com/gotd/td/bin"
+	"github.com/gotd/td/mt"
+	"github.com/gotd/td/proto"
+	"github.com/gotd/td/tg"
+)
+
+func TestSessionManagerSetClientLayerForAuthKey(t *testing.T) {
+	sm := NewSessionManager(zaptest.NewLogger(t))
+	c := &Conn{sessionID: 42, authKeyID: [8]byte{1, 2, 3}}
+	sm.Register(c)
+	defer sm.Unregister(c)
+
+	sm.SetClientLayerForAuthKey([8]byte{1, 2, 3}, 42, 225)
+	if got := c.ClientLayer(); got != 225 {
+		t.Fatalf("ClientLayer = %d, want 225", got)
+	}
+	// 未注册 session：no-op，不 panic。
+	sm.SetClientLayerForAuthKey([8]byte{9}, 1, 220)
+	// 非法 layer：忽略，保留已有值。
+	sm.SetClientLayerForAuthKey([8]byte{1, 2, 3}, 42, 0)
+	if got := c.ClientLayer(); got != 225 {
+		t.Fatalf("ClientLayer after layer=0 = %d, want 225", got)
+	}
+}
+
+type seededLayerRPC struct{}
+
+func (seededLayerRPC) Dispatch(context.Context, [8]byte, int64, *bin.Buffer) (bin.Encoder, error) {
+	return &tg.Config{ThisDC: 2}, nil
+}
+
+func (seededLayerRPC) NegotiatedLayer([8]byte, int64) (int, bool) { return 225, true }
+
+// TestRegisterSeedsNegotiatedLayerBeforeFirstRPC 验证连接注册即从 rpc 层播种协商 layer：
+// 只发一条 ping（服务消息，不经 RPC Dispatch），连接的 ClientLayer 就必须是协商值，
+// 而不是等首条 RPC 的 Dispatch 返回后才刷新——否则重连老客户端在首条 RPC handler
+// 执行期间收到的 pending flush / 并发 push 会按 canonical 227 漏降级。
+func TestRegisterSeedsNegotiatedLayerBeforeFirstRPC(t *testing.T) {
+	addr, pub, srv := startTestServer(t, Options{DC: 2, RPC: seededLayerRPC{}})
+	conn, auth, cipher := dialHandshake(t, addr, 2, pub)
+
+	clientMsgID := proto.NewMessageIDGen(time.Now)
+	sendEncrypted(t, conn, cipher, auth, clientMsgID.New(proto.MessageFromClient), &mt.PingRequest{PingID: 7})
+
+	// 等 pong 回来，确保携带注册动作的那一帧已处理完成。
+	gotPong := false
+	for i := 0; i < 12 && !gotPong; i++ {
+		_, id, _ := readServerMessage(t, conn, cipher, auth.AuthKey)
+		gotPong = id == mt.PongTypeID
+	}
+	if !gotPong {
+		t.Fatal("missing pong for ping")
+	}
+
+	srv.conns.mu.RLock()
+	c := srv.conns.bySession[sessionKey{authKeyID: auth.AuthKey.ID, sessionID: auth.SessionID}]
+	srv.conns.mu.RUnlock()
+	if c == nil {
+		t.Fatal("connection not registered")
+	}
+	if got := c.ClientLayer(); got != 225 {
+		t.Fatalf("ClientLayer after registration = %d, want seeded 225", got)
+	}
+}