From cfe205807ad0b72e3ad7c11cbff499d4ff06e73e Mon Sep 17 00:00:00 2001
From: Raz Luvaton <16746759+rluvaton@users.noreply.github.com>
Date: Sun, 17 Sep 2023 21:59:46 +0300
Subject: [PATCH 1/3] stream: improve readable webstream `pipeTo`

---
 lib/internal/webstreams/readablestream.js | 51 ++++++++++++++++-------
 1 file changed, 35 insertions(+), 16 deletions(-)

diff --git a/lib/internal/webstreams/readablestream.js b/lib/internal/webstreams/readablestream.js
index 28e985875c5ddb..f26b38c6aba9f2 100644
--- a/lib/internal/webstreams/readablestream.js
+++ b/lib/internal/webstreams/readablestream.js
@@ -1336,7 +1336,9 @@ function readableStreamPipeTo(
 
   const promise = createDeferredPromise();
 
-  let currentWrite = PromiseResolve();
+  const state = {
+    currentWrite: PromiseResolve(),
+  };
 
   // The error here can be undefined. The rejected arg
   // tells us that the promise must be rejected even
@@ -1353,9 +1355,9 @@ function readableStreamPipeTo(
   }
 
   async function waitForCurrentWrite() {
-    const write = currentWrite;
+    const write = state.currentWrite;
     await write;
-    if (write !== currentWrite)
+    if (write !== state.currentWrite)
       await waitForCurrentWrite();
   }
 
@@ -1446,20 +1448,15 @@ function readableStreamPipeTo(
   async function step() {
     if (shuttingDown)
       return true;
+
     await writer[kState].ready.promise;
-    return new Promise((resolve, reject) => {
-      readableStreamDefaultReaderRead(
-        reader,
-        {
-          [kChunk](chunk) {
-            currentWrite = writableStreamDefaultWriterWrite(writer, chunk);
-            setPromiseHandled(currentWrite);
-            resolve(false);
-          },
-          [kClose]: () => resolve(true),
-          [kError]: reject,
-        });
-    });
+
+    const promise = createDeferredPromise();
+    const readRequest = new PipeToReadableStreamReadRequest(writer, state, promise);
+
+    readableStreamDefaultReaderRead(reader, readRequest);
+
+    return promise.promise;
   }
 
   async function run() {
@@ -1521,6 +1518,28 @@ function readableStreamPipeTo(
   return promise.promise;
 }
 
+class PipeToReadableStreamReadRequest {
+  constructor(writer, state, promise) {
+    this.writer = writer;
+    this.state = state;
+    this.promise = promise;
+  }
+
+  [kChunk](chunk) {
+    this.state.currentWrite = writableStreamDefaultWriterWrite(this.writer, chunk);
+    setPromiseHandled(this.state.currentWrite);
+    this.promise.resolve(false);
+  }
+
+  [kClose]() {
+    this.promise.resolve(true)
+  }
+
+  [kError](error) {
+    this.promise.reject(error);
+  }
+}
+
 function readableStreamTee(stream, cloneForBranch2) {
   if (isReadableByteStreamController(stream[kState].controller)) {
     return readableByteStreamTee(stream);

From 3734af5c29d16ac78e901624faf133d7daf60594 Mon Sep 17 00:00:00 2001
From: Raz Luvaton <16746759+rluvaton@users.noreply.github.com>
Date: Sun, 17 Sep 2023 22:39:38 +0300
Subject: [PATCH 2/3] stream: fix lint

---
 lib/internal/webstreams/readablestream.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/internal/webstreams/readablestream.js b/lib/internal/webstreams/readablestream.js
index f26b38c6aba9f2..43c9eee924087d 100644
--- a/lib/internal/webstreams/readablestream.js
+++ b/lib/internal/webstreams/readablestream.js
@@ -14,7 +14,6 @@ const {
   ObjectCreate,
   ObjectDefineProperties,
   ObjectSetPrototypeOf,
-  Promise,
   PromisePrototypeThen,
   PromiseResolve,
   PromiseReject,
@@ -1452,6 +1451,7 @@ function readableStreamPipeTo(
     await writer[kState].ready.promise;
 
     const promise = createDeferredPromise();
+    // eslint-disable-next-line no-use-before-define
     const readRequest = new PipeToReadableStreamReadRequest(writer, state, promise);
 
     readableStreamDefaultReaderRead(reader, readRequest);
@@ -1532,7 +1532,7 @@ class PipeToReadableStreamReadRequest {
   }
 
   [kClose]() {
-    this.promise.resolve(true)
+    this.promise.resolve(true);
   }
 
   [kError](error) {

From fac8ca681a0dfe07e0289de27af83cdfff833f5c Mon Sep 17 00:00:00 2001
From: Raz Luvaton <16746759+rluvaton@users.noreply.github.com>
Date: Sun, 17 Sep 2023 22:57:16 +0300
Subject: [PATCH 3/3] stream: inline var

---
 lib/internal/webstreams/readablestream.js | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/lib/internal/webstreams/readablestream.js b/lib/internal/webstreams/readablestream.js
index 43c9eee924087d..924ffc34874111 100644
--- a/lib/internal/webstreams/readablestream.js
+++ b/lib/internal/webstreams/readablestream.js
@@ -1452,9 +1452,7 @@ function readableStreamPipeTo(
 
     const promise = createDeferredPromise();
     // eslint-disable-next-line no-use-before-define
-    const readRequest = new PipeToReadableStreamReadRequest(writer, state, promise);
-
-    readableStreamDefaultReaderRead(reader, readRequest);
+    readableStreamDefaultReaderRead(reader, new PipeToReadableStreamReadRequest(writer, state, promise));
 
     return promise.promise;
   }