fix tokio compatibility

Move it into async-global-executor

Fixes #881

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>

Cargo.toml

@@ -57,7 +57,7 @@ alloc = [
   "futures-core/alloc",
   "pin-project-lite",
 ]
-tokio02 = ["tokio"]
+tokio02 = ["async-global-executor/tokio02"]
 
 [dependencies]
 async-attributes = { version = "1.1.1", optional = true }
@@ -78,7 +78,7 @@ slab = { version = "0.4.2", optional = true }
 surf = { version = "1.0.3", optional = true }
 
 [target.'cfg(not(target_os = "unknown"))'.dependencies]
-async-global-executor = { version = "1.0.2", optional = true, features = ["async-io"] }
+async-global-executor = { version = "1.2.1", optional = true, features = ["async-io"] }
 async-io = { version = "1.0.1", optional = true }
 blocking = { version = "1.0.0", optional = true }
 futures-lite = { version = "1.0.0", optional = true }

src/task/builder.rs

@@ -168,7 +168,7 @@ impl Builder {
                 TaskLocalsWrapper::set_current(&wrapped.tag, || {
                     let res = if should_run {
                         // The first call should run the executor
-                        crate::task::executor::run(wrapped)
+                        async_global_executor::block_on(wrapped)
                     } else {
                         futures_lite::future::block_on(wrapped)
                     };

src/task/executor.rs

@@ -1,41 +0,0 @@
-use std::future::Future;
-
-pub(crate) fn run<F, T>(future: F) -> T
-where
-    F: Future<Output = T>,
-{
-    enter(|| async_global_executor::block_on(future))
-}
-
-/// Enters the tokio context if the `tokio` feature is enabled.
-fn enter<T>(f: impl FnOnce() -> T) -> T {
-    #[cfg(not(feature = "tokio02"))]
-    return f();
-
-    #[cfg(feature = "tokio02")]
-    {
-        use std::cell::Cell;
-        use tokio::runtime::Runtime;
-
-        thread_local! {
-            /// The level of nested `enter` calls we are in, to ensure that the outermost always
-            /// has a runtime spawned.
-            static NESTING: Cell<usize> = Cell::new(0);
-        }
-
-        /// The global tokio runtime.
-        static RT: once_cell::sync::Lazy<Runtime> = once_cell::sync::Lazy::new(|| Runtime::new().expect("cannot initialize tokio"));
-
-        NESTING.with(|nesting| {
-            let res = if nesting.get() == 0 {
-                nesting.replace(1);
-                RT.enter(f)
-            } else {
-                nesting.replace(nesting.get() + 1);
-                f()
-            };
-            nesting.replace(nesting.get() - 1);
-            res
-        })
-    }
-}

src/task/mod.rs

@@ -148,8 +148,6 @@ cfg_default! {
     mod block_on;
     mod builder;
     mod current;
-    #[cfg(not(target_os = "unknown"))]
-    pub(crate) mod executor;
     mod join_handle;
     mod sleep;
     #[cfg(not(target_os = "unknown"))]