Unregister channel from shortpoll.

Telegram/SourceFiles/api/api_updates.cpp

@@ -417,13 +417,12 @@ void Updates::channelDifferenceDone(
 			"{ good - after not final channelDifference was received }%1"
 			).arg(_session->mtp().isTestMode() ? " TESTMODE" : ""));
 		getChannelDifference(channel);
-	} else if (ranges::contains(
-			_activeChats,
-			channel,
-			[](const auto &pair) { return pair.second.peer; })) {
-		channel->ptsWaitingForShortPoll(timeout
+	} else if (inActiveChats(channel)) {
+		channel->ptsSetWaitingForShortPoll(timeout
 			? (timeout * crl::time(1000))
 			: kWaitForChannelGetDifference);
+	} else {
+		channel->ptsSetWaitingForShortPoll(-1);
 	}
 }
 
@@ -743,16 +742,32 @@ void Updates::addActiveChat(rpl::producer<PeerData*> chat) {
 	std::move(
 		chat
 	) | rpl::start_with_next_done([=](PeerData *peer) {
-		_activeChats[key].peer = peer;
-		if (const auto channel = peer ? peer->asChannel() : nullptr) {
-			channel->ptsWaitingForShortPoll(
-				kWaitForChannelGetDifference);
+		auto &active = _activeChats[key];
+		const auto was = active.peer;
+		if (was != peer) {
+			active.peer = peer;
+			if (const auto channel = was ? was->asChannel() : nullptr) {
+				if (!inActiveChats(channel)) {
+					channel->ptsSetWaitingForShortPoll(-1);
+				}
+			}
+			if (const auto channel = peer ? peer->asChannel() : nullptr) {
+				channel->ptsSetWaitingForShortPoll(
+					kWaitForChannelGetDifference);
+			}
 		}
 	}, [=] {
 		_activeChats.erase(key);
 	}, _activeChats[key].lifetime);
 }
 
+bool Updates::inActiveChats(not_null<PeerData*> peer) const {
+	return ranges::contains(
+		_activeChats,
+		peer.get(),
+		[](const auto &pair) { return pair.second.peer; });
+}
+
 void Updates::requestChannelRangeDifference(not_null<History*> history) {
 	Expects(history->peer->isChannel());
 

Telegram/SourceFiles/api/api_updates.h

@@ -63,6 +63,7 @@ public:
 	void requestChannelRangeDifference(not_null<History*> history);
 
 	void addActiveChat(rpl::producer<PeerData*> chat);
+	[[nodiscard]] bool inActiveChats(not_null<PeerData*> peer) const;
 
 private:
 	enum class ChannelDifferenceRequest {

Telegram/SourceFiles/apiwrap.cpp

@@ -2028,7 +2028,7 @@ void ApiWrap::deleteHistory(
 	}
 	if (const auto channel = peer->asChannel()) {
 		if (!justClear && !revoke) {
-			channel->ptsWaitingForShortPoll(-1);
+			channel->ptsSetWaitingForShortPoll(-1);
 			leaveChannel(channel);
 		} else {
 			if (const auto migrated = peer->migrateFrom()) {

Telegram/SourceFiles/data/data_channel.h

@@ -423,7 +423,7 @@ public:
 		return _ptsWaiter.setRequesting(isRequesting);
 	}
 	// < 0 - not waiting
-	void ptsWaitingForShortPoll(int32 ms) {
+	void ptsSetWaitingForShortPoll(int32 ms) {
 		return _ptsWaiter.setWaitingForShortPoll(this, ms);
 	}
 	[[nodiscard]] bool ptsWaitingForSkipped() const {