From 4e25008dd65034f99f1c15d2ecbdc0424ea283f7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fran=C3=A7ois?= <mockersf@gmail.com>
Date: Mon, 5 Jun 2023 22:54:12 +0200
Subject: [PATCH] correctly setup everything in the default run_once runner
 (#8740)

# Objective

- Fix #8658
- `without_winit` example panics `thread 'Compute Task Pool (2)'
panicked at 'called `Option::unwrap()` on a `None` value',
crates/bevy_render/src/pipelined_rendering.rs:134:84`

## Solution

- In the default runner method `run_once`, correctly finish the
initialisation of the plugins. `run_once` can't be called twice so it's
ok to do it there
---
 crates/bevy_app/Cargo.toml | 1 +
 crates/bevy_app/src/app.rs | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/crates/bevy_app/Cargo.toml b/crates/bevy_app/Cargo.toml
index 2a3f604e7b05f..89eec840c98e4 100644
--- a/crates/bevy_app/Cargo.toml
+++ b/crates/bevy_app/Cargo.toml
@@ -20,6 +20,7 @@ bevy_derive = { path = "../bevy_derive", version = "0.11.0-dev" }
 bevy_ecs = { path = "../bevy_ecs", version = "0.11.0-dev", default-features = false }
 bevy_reflect = { path = "../bevy_reflect", version = "0.11.0-dev", optional = true }
 bevy_utils = { path = "../bevy_utils", version = "0.11.0-dev" }
+bevy_tasks = { path = "../bevy_tasks", version = "0.11.0-dev" }
 
 # other
 serde = { version = "1.0", features = ["derive"], optional = true }
diff --git a/crates/bevy_app/src/app.rs b/crates/bevy_app/src/app.rs
index 613c5063df803..4a2c1eb58dc69 100644
--- a/crates/bevy_app/src/app.rs
+++ b/crates/bevy_app/src/app.rs
@@ -956,6 +956,13 @@ impl App {
 }
 
 fn run_once(mut app: App) {
+    while !app.ready() {
+        #[cfg(not(target_arch = "wasm32"))]
+        bevy_tasks::tick_global_task_pools_on_main_thread();
+    }
+    app.finish();
+    app.cleanup();
+
     app.update();
 }