Move async implementation into macro_internal

crates/neon-macros/src/export/function/mod.rs

@@ -64,24 +64,11 @@ pub(super) fn export(meta: meta::Meta, input: syn::ItemFn) -> proc_macro::TokenS
 
     // Generate the call to the original function
     let call_body = match meta.kind {
-        // TODO: Should this be moved inside of Neon in some way?
         Kind::Async => quote::quote!(
-            let rt = match neon::RUNTIME.get(&mut cx) {
-                Some(rt) => rt,
-                None => return neon::context::Context::throw_error(&mut cx, "neon::RUNTIME is not initialized"),
-            };
-
             let (#(#tuple_fields,)*) = cx.args()?;
-            let ch = neon::context::Context::channel(&mut cx);
-            let (d, promise) = neon::context::Context::promise(&mut cx);
             let fut = #name(#context_arg #(#args),*);
 
-            rt.spawn(Box::pin(async move {
-                let res = fut.await;
-                let _ = d.try_settle_with(&ch, move |mut cx| #result_extract);
-            }));
-
-            Ok(promise.upcast())
+            neon::macro_internal::spawn(&mut cx, fut, |mut cx, res| #result_extract)
         ),
         Kind::Normal => quote::quote!(
             let (#(#tuple_fields,)*) = cx.args()?;

crates/neon/src/macro_internal/futures.rs

@@ -0,0 +1,30 @@
+use std::future::Future;
+
+use crate::{
+    context::{Context, TaskContext},
+    result::JsResult,
+    types::JsValue,
+};
+
+pub fn spawn<'cx, C, F, S>(cx: &mut C, fut: F, settle: S) -> JsResult<'cx, JsValue>
+where
+    C: Context<'cx>,
+    F: Future + Send + 'static,
+    F::Output: Send,
+    S: FnOnce(TaskContext, F::Output) -> JsResult<JsValue> + Send + 'static,
+{
+    let rt = match crate::RUNTIME.get(cx) {
+        Some(rt) => rt,
+        None => return cx.throw_error("neon::RUNTIME is not initialized"),
+    };
+
+    let ch = cx.channel();
+    let (d, promise) = cx.promise();
+
+    rt.spawn(Box::pin(async move {
+        let res = fut.await;
+        let _ = d.try_settle_with(&ch, move |cx| settle(cx, res));
+    }));
+
+    Ok(promise.upcast())
+}

crates/neon/src/macro_internal/mod.rs

@@ -9,6 +9,12 @@ use crate::{
     types::{extract::TryIntoJs, JsValue},
 };
 
+#[cfg(all(feature = "napi-6", feature = "futures"))]
+pub use self::futures::spawn;
+
+#[cfg(all(feature = "napi-6", feature = "futures"))]
+mod futures;
+
 type Export<'cx> = (&'static str, Handle<'cx, JsValue>);
 
 #[linkme::distributed_slice]