From 0537c5f2739eaa0aef9492f426bb977e68afa47b Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Sat, 8 Mar 2025 07:05:45 +0400
Subject: [PATCH] Fix crashes in empty repaint callbacks.

---
 .../view/media/history_view_sticker_player.cpp       | 12 ++++++++++--
 .../userpic/info_userpic_emoji_builder_preview.cpp   |  2 +-
 .../SourceFiles/window/window_slide_animation.cpp    |  8 ++++++--
 3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/Telegram/SourceFiles/history/view/media/history_view_sticker_player.cpp b/Telegram/SourceFiles/history/view/media/history_view_sticker_player.cpp
index 64f6a883b..da9587057 100644
--- a/Telegram/SourceFiles/history/view/media/history_view_sticker_player.cpp
+++ b/Telegram/SourceFiles/history/view/media/history_view_sticker_player.cpp
@@ -21,6 +21,10 @@ LottiePlayer::LottiePlayer(std::unique_ptr<Lottie::SinglePlayer> lottie)
 }
 
 void LottiePlayer::setRepaintCallback(Fn<void()> callback) {
+	if (!callback) {
+		_repaintLifetime.destroy();
+		return;
+	}
 	_repaintLifetime = _lottie->updates(
 	) | rpl::start_with_next([=](Lottie::Update update) {
 		v::match(update.data, [&](const Lottie::Information &) {
@@ -82,7 +86,9 @@ void WebmPlayer::clipCallback(ClipNotification notification) {
 	case ClipNotification::Repaint: break;
 	}
 
-	_repaintCallback();
+	if (const auto onstack = _repaintCallback) {
+		onstack();
+	}
 }
 
 void WebmPlayer::setRepaintCallback(Fn<void()> callback) {
@@ -133,7 +139,9 @@ StaticStickerPlayer::StaticStickerPlayer(
 }
 
 void StaticStickerPlayer::setRepaintCallback(Fn<void()> callback) {
-	callback();
+	if (callback) {
+		callback();
+	}
 }
 
 bool StaticStickerPlayer::ready() {
diff --git a/Telegram/SourceFiles/info/userpic/info_userpic_emoji_builder_preview.cpp b/Telegram/SourceFiles/info/userpic/info_userpic_emoji_builder_preview.cpp
index 280b5c1b6..572809145 100644
--- a/Telegram/SourceFiles/info/userpic/info_userpic_emoji_builder_preview.cpp
+++ b/Telegram/SourceFiles/info/userpic/info_userpic_emoji_builder_preview.cpp
@@ -104,7 +104,7 @@ void PreviewPainter::setDocument(
 		}
 		if (_player) {
 			_player->setRepaintCallback(updateCallback);
-		} else {
+		} else if (updateCallback) {
 			updateCallback();
 		}
 	}, _lifetime);
diff --git a/Telegram/SourceFiles/window/window_slide_animation.cpp b/Telegram/SourceFiles/window/window_slide_animation.cpp
index 54a843559..fced2ba81 100644
--- a/Telegram/SourceFiles/window/window_slide_animation.cpp
+++ b/Telegram/SourceFiles/window/window_slide_animation.cpp
@@ -194,11 +194,15 @@ void SlideAnimation::start() {
 		fromLeft ? 0. : 1.,
 		st::slideDuration,
 		transition());
-	_repaintCallback();
+	if (const auto onstack = _repaintCallback) {
+		onstack();
+	}
 }
 
 void SlideAnimation::animationCallback() {
-	_repaintCallback();
+	if (const auto onstack = _repaintCallback) {
+		onstack();
+	}
 	if (!_animation.animating()) {
 		if (const auto onstack = _finishedCallback) {
 			onstack();