1 files changed, 43 insertions, 30 deletions

diff --git a/ext/io/lib.rs b/ext/io/lib.rs
index eb26c495a..038176b23 100644
--- a/ext/io/lib.rs
+++ b/ext/io/lib.rs
@@ -3,6 +3,7 @@
 use deno_core::error::AnyError;
 use deno_core::op2;
 use deno_core::unsync::spawn_blocking;
+use deno_core::unsync::TaskQueue;
 use deno_core::AsyncMutFuture;
 use deno_core::AsyncRefCell;
 use deno_core::AsyncResult;
@@ -16,7 +17,6 @@ use deno_core::RcRef;
 use deno_core::Resource;
 use deno_core::ResourceHandle;
 use deno_core::ResourceHandleFd;
-use deno_core::TaskQueue;
 use fs::FileResource;
 use fs::FsError;
 use fs::FsResult;
@@ -26,6 +26,7 @@ use once_cell::sync::Lazy;
 use std::borrow::Cow;
 use std::cell::RefCell;
 use std::fs::File as StdFile;
+use std::future::Future;
 use std::io;
 use std::io::ErrorKind;
 use std::io::Read;
@@ -309,7 +310,7 @@ pub struct StdFileResourceInner {
   cell: RefCell<Option<StdFile>>,
   // Used to keep async actions in order and only allow one
   // to occur at a time
-  cell_async_task_queue: TaskQueue,
+  cell_async_task_queue: Rc<TaskQueue>,
   handle: ResourceHandleFd,
 }
 
@@ -339,48 +340,60 @@ impl StdFileResourceInner {
     }
   }
 
-  async fn with_inner_blocking_task<F, R: 'static + Send>(&self, action: F) -> R
+  fn with_inner_blocking_task<F, R: 'static + Send>(
+    &self,
+    action: F,
+  ) -> impl Future<Output = R> + '_
   where
     F: FnOnce(&mut StdFile) -> R + Send + 'static,
   {
     // we want to restrict this to one async action at a time
-    let _permit = self.cell_async_task_queue.acquire().await;
-    // we take the value out of the cell, use it on a blocking task,
-    // then put it back into the cell when we're done
-    let mut did_take = false;
-    let mut cell_value = {
-      let mut cell = self.cell.borrow_mut();
-      match cell.as_mut().unwrap().try_clone().ok() {
-        Some(value) => value,
-        None => {
-          did_take = true;
-          cell.take().unwrap()
+    let acquire_fut = self.cell_async_task_queue.acquire();
+    async move {
+      let permit = acquire_fut.await;
+      // we take the value out of the cell, use it on a blocking task,
+      // then put it back into the cell when we're done
+      let mut did_take = false;
+      let mut cell_value = {
+        let mut cell = self.cell.borrow_mut();
+        match cell.as_mut().unwrap().try_clone().ok() {
+          Some(value) => value,
+          None => {
+            did_take = true;
+            cell.take().unwrap()
+          }
         }
+      };
+      let (cell_value, result) = spawn_blocking(move || {
+        let result = action(&mut cell_value);
+        (cell_value, result)
+      })
+      .await
+      .unwrap();
+
+      if did_take {
+        // put it back
+        self.cell.borrow_mut().replace(cell_value);
       }
-    };
-    let (cell_value, result) = spawn_blocking(move || {
-      let result = action(&mut cell_value);
-      (cell_value, result)
-    })
-    .await
-    .unwrap();
 
-    if did_take {
-      // put it back
-      self.cell.borrow_mut().replace(cell_value);
+      drop(permit); // explicit for clarity
+      result
     }
-
-    result
   }
 
-  async fn with_blocking_task<F, R: 'static + Send>(&self, action: F) -> R
+  fn with_blocking_task<F, R: 'static + Send>(
+    &self,
+    action: F,
+  ) -> impl Future<Output = R>
   where
     F: FnOnce() -> R + Send + 'static,
   {
     // we want to restrict this to one async action at a time
-    let _permit = self.cell_async_task_queue.acquire().await;
-
-    spawn_blocking(action).await.unwrap()
+    let acquire_fut = self.cell_async_task_queue.acquire();
+    async move {
+      let _permit = acquire_fut.await;
+      spawn_blocking(action).await.unwrap()
+    }
   }
 }