2 files changed, 21 insertions, 29 deletions

diff --git a/core/modules.rs b/core/modules.rs
index 546f2464f..8248eb32d 100644
--- a/core/modules.rs
+++ b/core/modules.rs
@@ -718,8 +718,8 @@ mod tests {
     let spec = ModuleSpecifier::resolve_url("file:///a.js").unwrap();
     let a_id_fut = runtime.load_module(&spec, None);
     let a_id = futures::executor::block_on(a_id_fut).expect("Failed to load");
-
-    futures::executor::block_on(runtime.mod_evaluate(a_id)).unwrap();
+    runtime.mod_evaluate(a_id);
+    futures::executor::block_on(runtime.run_event_loop()).unwrap();
     let l = loads.lock().unwrap();
     assert_eq!(
       l.to_vec(),
@@ -786,7 +786,8 @@ mod tests {
       let result = runtime.load_module(&spec, None).await;
       assert!(result.is_ok());
       let circular1_id = result.unwrap();
-      runtime.mod_evaluate(circular1_id).await.unwrap();
+      runtime.mod_evaluate(circular1_id);
+      runtime.run_event_loop().await.unwrap();
 
       let l = loads.lock().unwrap();
       assert_eq!(
@@ -863,7 +864,8 @@ mod tests {
       println!(">> result {:?}", result);
       assert!(result.is_ok());
       let redirect1_id = result.unwrap();
-      runtime.mod_evaluate(redirect1_id).await.unwrap();
+      runtime.mod_evaluate(redirect1_id);
+      runtime.run_event_loop().await.unwrap();
       let l = loads.lock().unwrap();
       assert_eq!(
         l.to_vec(),
@@ -1012,8 +1014,8 @@ mod tests {
       .boxed_local();
     let main_id =
       futures::executor::block_on(main_id_fut).expect("Failed to load");
-
-    futures::executor::block_on(runtime.mod_evaluate(main_id)).unwrap();
+    runtime.mod_evaluate(main_id);
+    futures::executor::block_on(runtime.run_event_loop()).unwrap();
 
     let l = loads.lock().unwrap();
     assert_eq!(
diff --git a/core/runtime.rs b/core/runtime.rs
index 24bdf4dc2..e9949bc8e 100644
--- a/core/runtime.rs
+++ b/core/runtime.rs
@@ -825,12 +825,17 @@ impl JsRuntime {
     Ok(())
   }
 
+  // TODO(bartlomieju): make it return `ModuleEvaluationFuture`?
   /// Evaluates an already instantiated ES module.
   ///
+  /// Returns a receiver handle that resolves when module promise resolves.
+  /// Implementors must manually call `run_event_loop()` to drive module
+  /// evaluation future.
+  ///
   /// `AnyError` can be downcast to a type that exposes additional information
   /// about the V8 exception. By default this type is `JsError`, however it may
   /// be a different type if `RuntimeOptions::js_error_create_fn` has been set.
-  fn mod_evaluate_inner(
+  pub fn mod_evaluate(
     &mut self,
     id: ModuleId,
   ) -> mpsc::Receiver<Result<(), AnyError>> {
@@ -902,24 +907,6 @@ impl JsRuntime {
     receiver
   }
 
-  pub async fn mod_evaluate(&mut self, id: ModuleId) -> Result<(), AnyError> {
-    let mut receiver = self.mod_evaluate_inner(id);
-
-    poll_fn(|cx| {
-      if let Poll::Ready(maybe_result) = receiver.poll_next_unpin(cx) {
-        debug!("received module evaluate {:#?}", maybe_result);
-        // If `None` is returned it means that runtime was destroyed before
-        // evaluation was complete. This can happen in Web Worker when `self.close()`
-        // is called at top level.
-        let result = maybe_result.unwrap_or(Ok(()));
-        return Poll::Ready(result);
-      }
-      let _r = self.poll_event_loop(cx)?;
-      Poll::Pending
-    })
-    .await
-  }
-
   fn dyn_import_error(&mut self, id: ModuleLoadId, err: AnyError) {
     let state_rc = Self::state(self.v8_isolate());
     let context = self.global_context();
@@ -1110,7 +1097,8 @@ impl JsRuntime {
           v8::PromiseState::Fulfilled => {
             state.pending_mod_evaluate.take();
             scope.perform_microtask_checkpoint();
-            sender.try_send(Ok(())).unwrap();
+            // Receiver end might have been already dropped, ignore the result
+            let _ = sender.try_send(Ok(()));
           }
           v8::PromiseState::Rejected => {
             let exception = promise.result(scope);
@@ -1120,7 +1108,8 @@ impl JsRuntime {
             let err1 = exception_to_err_result::<()>(scope, exception, false)
               .map_err(|err| attach_handle_to_error(scope, err, exception))
               .unwrap_err();
-            sender.try_send(Err(err1)).unwrap();
+            // Receiver end might have been already dropped, ignore the result
+            let _ = sender.try_send(Err(err1));
           }
         }
       }
@@ -2259,7 +2248,7 @@ pub mod tests {
     runtime.mod_instantiate(mod_a).unwrap();
     assert_eq!(dispatch_count.load(Ordering::Relaxed), 0);
 
-    runtime.mod_evaluate_inner(mod_a);
+    runtime.mod_evaluate(mod_a);
     assert_eq!(dispatch_count.load(Ordering::Relaxed), 1);
   }
 
@@ -2502,7 +2491,8 @@ pub mod tests {
     )
     .unwrap();
 
-    futures::executor::block_on(runtime.mod_evaluate(module_id)).unwrap();
+    runtime.mod_evaluate(module_id);
+    futures::executor::block_on(runtime.run_event_loop()).unwrap();
 
     let _snapshot = runtime.snapshot();
   }