Make GatedReader a test-only symbol, and allow all bevy_asset tests to all run single threaded.

crates/bevy_asset/Cargo.toml

@@ -91,6 +91,9 @@ bevy_reflect = { path = "../bevy_reflect", version = "0.17.0-dev", default-featu
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 notify-debouncer-full = { version = "0.5.0", default-features = false, optional = true }
 
+[dev-dependencies]
+async-channel = "2"
+
 [lints]
 workspace = true
 

crates/bevy_asset/src/io/gated.rs

@@ -1,7 +1,7 @@
 use crate::io::{AssetReader, AssetReaderError, PathStream, Reader};
 use alloc::{boxed::Box, sync::Arc};
+use async_channel::{Receiver, Sender};
 use bevy_platform::collections::HashMap;
-use crossbeam_channel::{Receiver, Sender};
 use parking_lot::RwLock;
 use std::path::Path;
 
@@ -35,8 +35,8 @@ impl GateOpener {
         let mut gates = self.gates.write();
         let gates = gates
             .entry_ref(path.as_ref())
-            .or_insert_with(crossbeam_channel::unbounded);
-        gates.0.send(()).unwrap();
+            .or_insert_with(async_channel::unbounded);
+        gates.0.send_blocking(()).unwrap();
     }
 }
 
@@ -61,10 +61,10 @@ impl<R: AssetReader> AssetReader for GatedReader<R> {
             let mut gates = self.gates.write();
             let gates = gates
                 .entry_ref(path.as_ref())
-                .or_insert_with(crossbeam_channel::unbounded);
+                .or_insert_with(async_channel::unbounded);
             gates.1.clone()
         };
-        receiver.recv().unwrap();
+        receiver.recv().await.unwrap();
         let result = self.reader.read(path).await?;
         Ok(result)
     }

crates/bevy_asset/src/io/mod.rs

@@ -10,12 +10,14 @@ pub mod android;
 pub mod embedded;
 #[cfg(not(target_arch = "wasm32"))]
 pub mod file;
-pub mod gated;
 pub mod memory;
 pub mod processor_gated;
 #[cfg(target_arch = "wasm32")]
 pub mod wasm;
 
+#[cfg(test)]
+pub mod gated;
+
 mod source;
 
 pub use futures_lite::AsyncWriteExt;

crates/bevy_asset/src/lib.rs

@@ -894,10 +894,6 @@ mod tests {
 
     #[test]
     fn load_dependencies() {
-        // The particular usage of GatedReader in this test will cause deadlocking if running single-threaded
-        #[cfg(not(feature = "multi_threaded"))]
-        panic!("This test requires the \"multi_threaded\" feature, otherwise it will deadlock.\ncargo test --package bevy_asset --features multi_threaded");
-
         let dir = Dir::default();
 
         let a_path = "a.cool.ron";
@@ -1202,10 +1198,6 @@ mod tests {
 
     #[test]
     fn failure_load_states() {
-        // The particular usage of GatedReader in this test will cause deadlocking if running single-threaded
-        #[cfg(not(feature = "multi_threaded"))]
-        panic!("This test requires the \"multi_threaded\" feature, otherwise it will deadlock.\ncargo test --package bevy_asset --features multi_threaded");
-
         let dir = Dir::default();
 
         let a_path = "a.cool.ron";
@@ -1335,10 +1327,6 @@ mod tests {
 
     #[test]
     fn dependency_load_states() {
-        // The particular usage of GatedReader in this test will cause deadlocking if running single-threaded
-        #[cfg(not(feature = "multi_threaded"))]
-        panic!("This test requires the \"multi_threaded\" feature, otherwise it will deadlock.\ncargo test --package bevy_asset --features multi_threaded");
-
         let a_path = "a.cool.ron";
         let a_ron = r#"
 (
@@ -1474,10 +1462,6 @@ mod tests {
 
     #[test]
     fn manual_asset_management() {
-        // The particular usage of GatedReader in this test will cause deadlocking if running single-threaded
-        #[cfg(not(feature = "multi_threaded"))]
-        panic!("This test requires the \"multi_threaded\" feature, otherwise it will deadlock.\ncargo test --package bevy_asset --features multi_threaded");
-
         let dir = Dir::default();
         let dep_path = "dep.cool.ron";
 
@@ -1575,10 +1559,6 @@ mod tests {
 
     #[test]
     fn load_folder() {
-        // The particular usage of GatedReader in this test will cause deadlocking if running single-threaded
-        #[cfg(not(feature = "multi_threaded"))]
-        panic!("This test requires the \"multi_threaded\" feature, otherwise it will deadlock.\ncargo test --package bevy_asset --features multi_threaded");
-
         let dir = Dir::default();
 
         let a_path = "text/a.cool.ron";