From 28eb4f6247bd3a6bc75b2878158ca8f68cc20c6f Mon Sep 17 00:00:00 2001
From: Mike Hsu <mike.hsu@gmail.com>
Date: Mon, 30 Jan 2023 17:02:49 -0800
Subject: [PATCH] change exclusive systems too

---
 .../src/scheduling/executor/multi_threaded.rs | 38 +++++++++++++------
 1 file changed, 27 insertions(+), 11 deletions(-)

diff --git a/crates/bevy_ecs/src/scheduling/executor/multi_threaded.rs b/crates/bevy_ecs/src/scheduling/executor/multi_threaded.rs
index 51d6d301fed65..ad2fbe8822470 100644
--- a/crates/bevy_ecs/src/scheduling/executor/multi_threaded.rs
+++ b/crates/bevy_ecs/src/scheduling/executor/multi_threaded.rs
@@ -186,7 +186,7 @@ impl SystemExecutor for MultiThreadedExecutor {
                                 .receiver
                                 .recv()
                                 .await
-                                .expect("a system has panicked and closed the channel");
+                                .expect("A system has panicked so the executor cannot continue.");
 
                             self.finish_system_and_signal_dependents(index);
 
@@ -492,13 +492,21 @@ impl MultiThreadedExecutor {
             let task = async move {
                 #[cfg(feature = "trace")]
                 let system_guard = system_span.enter();
-                apply_system_buffers(&mut unapplied_systems, systems, world);
+                let res = std::panic::catch_unwind(AssertUnwindSafe(|| {
+                    apply_system_buffers(&mut unapplied_systems, systems, world);
+                }));
                 #[cfg(feature = "trace")]
                 drop(system_guard);
-                sender
-                    .send(system_index)
-                    .await
-                    .unwrap_or_else(|error| unreachable!("{}", error));
+                if res.is_err() {
+                    // close the channel to propagate the error to the
+                    // multithreaded executor
+                    sender.close();
+                } else {
+                    sender
+                        .send(system_index)
+                        .await
+                        .unwrap_or_else(|error| unreachable!("{}", error));
+                }
             };
 
             #[cfg(feature = "trace")]
@@ -508,13 +516,21 @@ impl MultiThreadedExecutor {
             let task = async move {
                 #[cfg(feature = "trace")]
                 let system_guard = system_span.enter();
-                system.run((), world);
+                let res = std::panic::catch_unwind(AssertUnwindSafe(|| {
+                    system.run((), world);
+                }));
                 #[cfg(feature = "trace")]
                 drop(system_guard);
-                sender
-                    .send(system_index)
-                    .await
-                    .unwrap_or_else(|error| unreachable!("{}", error));
+                if res.is_err() {
+                    // close the channel to propagate the error to the
+                    // multithreaded executor
+                    sender.close();
+                } else {
+                    sender
+                        .send(system_index)
+                        .await
+                        .unwrap_or_else(|error| unreachable!("{}", error));
+                }
             };
 
             #[cfg(feature = "trace")]