From 33d42034fc7f103bf6520e8f3fa35cd8dbc01254 Mon Sep 17 00:00:00 2001
From: Orion Kindel <orionkindel@gmail.com>
Date: Tue, 14 May 2024 13:51:57 -0500
Subject: [PATCH] fix: continue to read after readableEnded

---
 src/Node.Stream.Object.js   | 16 ++++------------
 src/Node.Stream.Object.purs | 10 ++++------
 src/Pipes.Node.Stream.purs  | 36 ++++++++++++++++++++++--------------
 3 files changed, 30 insertions(+), 32 deletions(-)

diff --git a/src/Node.Stream.Object.js b/src/Node.Stream.Object.js
index db8ee5e..37b3c99 100644
--- a/src/Node.Stream.Object.js
+++ b/src/Node.Stream.Object.js
@@ -24,16 +24,12 @@ export const isWritableEndedImpl = (s) => () => s.writableEnded;
 /** @type {(s: Stream.Writable | Stream.Transform) => () => void} */
 export const endImpl = (s) => () => s.end();
 
-/** @type {<WriteResult>(o: {ok: WriteResult, wouldBlock: WriteResult, closed: WriteResult}) => (s: Stream.Writable | Stream.Transform) => (a: unknown) => () => WriteResult} */
+/** @type {<WriteResult>(o: {ok: WriteResult, wouldBlock: WriteResult}) => (s: Stream.Writable | Stream.Transform) => (a: unknown) => () => WriteResult} */
 export const writeImpl =
-  ({ ok, wouldBlock, closed }) =>
+  ({ ok, wouldBlock }) =>
   (s) =>
   (a) =>
   () => {
-    if (s.writableEnded) {
-      return closed;
-    }
-
     if (s.write(a)) {
       return ok;
     } else {
@@ -41,15 +37,11 @@ export const writeImpl =
     }
   };
 
-/** @type {<ReadResult>(o: {just: (_a: unknown) => ReadResult, wouldBlock: ReadResult, closed: ReadResult}) => (s: Stream.Readable | Stream.Transform) => () => ReadResult} */
+/** @type {<ReadResult>(o: {just: (_a: unknown) => ReadResult, wouldBlock: ReadResult}) => (s: Stream.Readable | Stream.Transform) => () => ReadResult} */
 export const readImpl =
-  ({ just, closed, wouldBlock }) =>
+  ({ just, wouldBlock }) =>
   (s) =>
   () => {
-    if (s.readableEnded) {
-      return closed;
-    }
-
     const a = s.read();
     if (a === null) {
       return wouldBlock;
diff --git a/src/Node.Stream.Object.purs b/src/Node.Stream.Object.purs
index ac55465..55fed8b 100644
--- a/src/Node.Stream.Object.purs
+++ b/src/Node.Stream.Object.purs
@@ -26,7 +26,6 @@ import Unsafe.Coerce (unsafeCoerce)
 
 data ReadResult a
   = ReadWouldBlock
-  | ReadClosed
   | ReadJust a
 
 derive instance Generic (ReadResult a) _
@@ -37,7 +36,6 @@ instance Show (ReadResult a) where
 
 data WriteResult
   = WriteWouldBlock
-  | WriteClosed
   | WriteOk
 
 derive instance Generic WriteResult _
@@ -45,8 +43,8 @@ derive instance Eq WriteResult
 instance Show WriteResult where
   show = genericShow
 
-type ReadResultFFI a = { closed :: ReadResult a, wouldBlock :: ReadResult a, just :: a -> ReadResult a }
-type WriteResultFFI = { closed :: WriteResult, wouldBlock :: WriteResult, ok :: WriteResult }
+type ReadResultFFI a = { wouldBlock :: ReadResult a, just :: a -> ReadResult a }
+type WriteResultFFI = { wouldBlock :: WriteResult, ok :: WriteResult }
 
 foreign import data Writable :: Type -> Type
 foreign import data Readable :: Type -> Type
@@ -64,10 +62,10 @@ foreign import needsDrainImpl :: forall s. s -> Effect Boolean
 foreign import readableLengthImpl :: forall s. s -> Effect Int
 
 readResultFFI :: forall a. ReadResultFFI a
-readResultFFI = { closed: ReadClosed, wouldBlock: ReadWouldBlock, just: ReadJust }
+readResultFFI = { wouldBlock: ReadWouldBlock, just: ReadJust }
 
 writeResultFFI :: WriteResultFFI
-writeResultFFI = { closed: WriteClosed, wouldBlock: WriteWouldBlock, ok: WriteOk }
+writeResultFFI = { wouldBlock: WriteWouldBlock, ok: WriteOk }
 
 class Stream :: Type -> Constraint
 class Stream s where
diff --git a/src/Pipes.Node.Stream.purs b/src/Pipes.Node.Stream.purs
index f7be32f..39d1af3 100644
--- a/src/Pipes.Node.Stream.purs
+++ b/src/Pipes.Node.Stream.purs
@@ -40,8 +40,13 @@ fromReadable r =
       res <- liftEffect $ O.read r
       case res of
         O.ReadJust a -> yield (Just a) $> Loop { error, cancel }
-        O.ReadWouldBlock -> liftAff (O.awaitReadableOrClosed r) $> Loop { error, cancel }
-        O.ReadClosed -> yield Nothing *> cleanup cancel
+        O.ReadWouldBlock -> do
+          ended <- liftEffect $ O.isReadableEnded r
+          if ended then do
+            yield Nothing
+            cleanup cancel
+          else
+            liftAff (O.awaitReadableOrClosed r) $> Loop { error, cancel }
   in
     do
       e <- liftEffect $ O.withErrorST r
@@ -66,14 +71,16 @@ fromWritable w =
 
       needsDrain <- liftEffect $ O.needsDrain w
       when needsDrain $ liftAff $ O.awaitWritableOrClosed w
-      ma <- await
-      case ma of
-        Nothing -> cleanup cancel
-        Just a -> do
-          res <- liftEffect $ O.write w a
-          case res of
-            O.WriteClosed -> cleanup cancel
-            _ -> pure $ Loop { error, cancel }
+
+      ended <- liftEffect $ O.isWritableEnded w
+      if ended then
+        cleanup cancel
+      else
+        await >>= case _ of
+          Nothing -> cleanup cancel
+          Just a -> do
+            void $ liftEffect $ O.write w a
+            pure $ Loop { error, cancel }
   in
     do
       r <- liftEffect $ O.withErrorST w
@@ -111,18 +118,19 @@ fromTransform t =
       for_ err throwError
 
       needsDrain <- liftEffect $ O.needsDrain t
+      ended <- liftEffect $ O.isWritableEnded t
       if needsDrain then do
         liftAff $ delay $ wrap 0.0
         yieldWhileReadable
         pure $ Loop { error, cancel }
-      else do
-        ma <- await
-        case ma of
+      else if ended then
+        cleanup cancel
+      else
+        await >>= case _ of
           Nothing -> cleanup cancel
           Just a' -> do
             res <- liftEffect $ O.write t a'
             case res of
-              O.WriteClosed -> cleanup cancel
               O.WriteOk -> do
                 maybeYield1
                 pure $ Loop { error, cancel }