From f9256fa132e9d3c50ef1e1eafe2774160b38e063 Mon Sep 17 00:00:00 2001
From: Conner <72773002+XNUConner@users.noreply.github.com>
Date: Sun, 22 May 2022 08:37:27 -0500
Subject: [PATCH] Fix PostEvent() segfault (#403)

Fix segfault when PostEvent() called on inactive screen.

Co-authored-by: ArthurSonzogni <sonzogniarthur@gmail.com>
---
 src/ftxui/component/screen_interactive.cpp      | 10 +++++++---
 src/ftxui/component/screen_interactive_test.cpp | 14 ++++++++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/ftxui/component/screen_interactive.cpp b/src/ftxui/component/screen_interactive.cpp
index 8a7b4e08..674276f7 100644
--- a/src/ftxui/component/screen_interactive.cpp
+++ b/src/ftxui/component/screen_interactive.cpp
@@ -295,10 +295,14 @@ ScreenInteractive ScreenInteractive::FitComponent() {
 }
 
 void ScreenInteractive::Post(Task task) {
-  if (!quit_) {
-    task_sender_->Send(std::move(task));
-  }
+  // Task/Events sent toward inactive screen or screen waiting to become
+  // inactive are dropped.
+  if (!task_sender_)
+    return;
+
+  task_sender_->Send(std::move(task));
 }
+
 void ScreenInteractive::PostEvent(Event event) {
   Post(event);
 }
diff --git a/src/ftxui/component/screen_interactive_test.cpp b/src/ftxui/component/screen_interactive_test.cpp
index 9592d932..957e98b1 100644
--- a/src/ftxui/component/screen_interactive_test.cpp
+++ b/src/ftxui/component/screen_interactive_test.cpp
@@ -47,6 +47,20 @@ TEST(ScreenInteractive, Signal_SIGFPE) {
   TestSignal(SIGFPE);
 }
 
+// Regression test for:
+// https://github.com/ArthurSonzogni/FTXUI/issues/402
+TEST(ScreenInteractive, PostEventToNonActive) {
+  auto screen = ScreenInteractive::FitComponent();
+  screen.Post(Event::Custom);
+}
+
+// Regression test for:
+// https://github.com/ArthurSonzogni/FTXUI/issues/402
+TEST(ScreenInteractive, PostTaskToNonActive) {
+  auto screen = ScreenInteractive::FitComponent();
+  screen.Post([] {});
+}
+
 }  // namespace ftxui
 
 // Copyright 2021 Arthur Sonzogni. All rights reserved.