fix(messages): sync Android pinned message search

internal/rpc/channels_multi_pin_android_rpc_test.go

@@ -97,12 +97,17 @@ func TestChannelMultiPinAndroidOpenAndJump(t *testing.T) {
 	}
 
 	// ① 打开聊天：MediaDataController.loadPinnedMessages → messages.search filterPinned。
-	searchEnc := dispatch(&tg.MessagesSearchRequest{
+	androidPinnedSearch := &tg.MessagesSearchRequest{
 		Peer:   peer,
 		Q:      "",
 		Filter: &tg.InputMessagesFilterPinned{},
 		Limit:  40,
-	})
+	}
+	// DrKLO initializes saved_reaction to an empty non-nil ArrayList and its
+	// serializer consequently emits flags.3 + Vector length 0 on every
+	// messages.search, including channel filterPinned.
+	androidPinnedSearch.SetSavedReaction([]tg.ReactionClass{})
+	searchEnc := dispatch(androidPinnedSearch)
 	channelMessages, ok := searchEnc.(*tg.MessagesChannelMessages)
 	if !ok {
 		t.Fatalf("pinned search response = %T, want messages.channelMessages", searchEnc)

internal/rpc/messages_history.go

@@ -804,8 +804,13 @@ func (r *Router) messageFilterFromSearchRequest(ctx context.Context, userID int6
 		filter.Peer = peer
 	}
 	savedReactions, hasSavedReactions := req.GetSavedReaction()
+	// An empty optional vector carries no reaction-filtering semantics. Some TL
+	// clients emit flags.3 with a zero-length vector on ordinary peer searches.
+	// Keep the wire presence intact at the TL edge, but only apply Saved
+	// Messages scope and reaction validation when the vector has values.
+	hasSavedReactionFilter := hasSavedReactions && len(savedReactions) > 0
 	savedPeerInput, hasSavedPeer := req.GetSavedPeerID()
-	if hasSavedReactions || hasSavedPeer {
+	if hasSavedReactionFilter || hasSavedPeer {
 		if !filter.HasPeer ||
 			filter.Peer != (domain.Peer{Type: domain.PeerTypeUser, ID: userID}) {
 			return domain.MessageFilter{}, peerIDInvalidErr()
@@ -821,8 +826,8 @@ func (r *Router) messageFilterFromSearchRequest(ctx context.Context, userID int6
 		}
 		filter.SavedPeer = savedPeer
 	}
-	if hasSavedReactions {
+	if hasSavedReactionFilter {
-		if len(savedReactions) == 0 || len(savedReactions) > maxReactionVector {
+		if len(savedReactions) > maxReactionVector {
 			return domain.MessageFilter{}, reactionInvalidErr()
 		}
 		seen := make(map[string]struct{}, len(savedReactions))

internal/rpc/messages_history_rpc_test.go

@@ -225,6 +225,9 @@ func TestMessagesSearchChannelPeerReturnsSingleCopyMessages(t *testing.T) {
 		Filter: &tg.InputMessagesFilterPhotos{},
 		Limit:  0,
 	}
+	// Match DrKLO's ordinary messages.search wire shape: flags.3 is present
+	// even though the saved_reaction vector is empty.
+	mediaCountReq.SetSavedReaction([]tg.ReactionClass{})
 	in.Reset()
 	if err := mediaCountReq.Encode(&in); err != nil {
 		t.Fatalf("encode shared media count search: %v", err)

internal/rpc/messages_reactions_test.go

@@ -234,6 +234,23 @@ func TestMessageFilterFromSearchRequestParsesSavedTagsAndPeer(t *testing.T) {
 	if _, err := r.messageFilterFromSearchRequest(WithUserID(context.Background(), userID), userID, req); !tgerr.Is(err, "PEER_ID_INVALID") {
 		t.Fatalf("non-self saved search err = %v, want PEER_ID_INVALID", err)
 	}
+
+	emptyTagReq := &tg.MessagesSearchRequest{
+		Peer:   &tg.InputPeerUser{UserID: userID + 1, AccessHash: 1},
+		Q:      "ordinary",
+		Filter: &tg.InputMessagesFilterEmpty{},
+		Limit:  20,
+	}
+	emptyTagReq.SetSavedReaction([]tg.ReactionClass{})
+	ordinary, err := r.messageFilterFromSearchRequest(WithUserID(context.Background(), userID), userID, emptyTagReq)
+	if err != nil {
+		t.Fatalf("empty saved reaction on ordinary peer search: %v", err)
+	}
+	if !ordinary.HasPeer ||
+		ordinary.Peer != (domain.Peer{Type: domain.PeerTypeUser, ID: userID + 1}) ||
+		len(ordinary.SavedReactions) != 0 {
+		t.Fatalf("ordinary peer filter with empty saved reaction = %+v", ordinary)
+	}
 }
 
 func TestMessagesGetDefaultTagReactionsReturnsHashableCatalog(t *testing.T) {