allowAsyncOps applies to async file flushing as well

faststreams/outputs.nim

@@ -273,6 +273,14 @@ let fileOutputVTable = OutputStreamVTable(
                   {.nimcall, gcsafe, raises: [IOError, Defect].} =
     flushFile FileOutputStream(s).file
   ,
+  flushAsync: proc (s: OutputStream): Future[void]
+                   {.nimcall, gcsafe, raises: [IOError, Defect].} =
+    fsAssert FileOutputStream(s).allowAsyncOps
+    flushFile FileOutputStream(s).file
+    result = newFuture[void]()
+    fsTranslateErrors "Unexpected exception from merely completing a future":
+      result.complete()
+  ,
   closeSync: proc (s: OutputStream)
                   {.nimcall, gcsafe, raises: [IOError, Defect].} =
     close FileOutputStream(s).file

faststreams/pipelines.nim

@@ -127,7 +127,7 @@ when fsAsyncSupport:
         flush destination
     ,
     flushAsync: proc (s: OutputStream): Future[void]
-                    {.nimcall, gcsafe, raises: [IOError, Defect].} =
+                     {.nimcall, gcsafe, raises: [IOError, Defect].} =
       fsTranslateErrors "Unexpected error from the async macro":
         let destination = LayeredOutputStream(s).destination
         if destination != nil: