From 5c23d670a37e33517403087d64869acbf93bccde Mon Sep 17 00:00:00 2001
From: Jarred Sumner <jarred@jarredsumner.com>
Date: Sun, 26 Nov 2023 11:11:42 +0100
Subject: [PATCH] Fix bug with readable streams that have been detached (#7308)

Co-authored-by: Jarred Sumner <709451+Jarred-Sumner@users.noreply.github.com>
---
 src/js/builtins/ReadableStreamInternals.ts | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/src/js/builtins/ReadableStreamInternals.ts b/src/js/builtins/ReadableStreamInternals.ts
index 36f049f3ec2ef5..eee2c41864eb00 100644
--- a/src/js/builtins/ReadableStreamInternals.ts
+++ b/src/js/builtins/ReadableStreamInternals.ts
@@ -1259,10 +1259,11 @@ export function readableStreamError(stream, error) {
 }
 
 export function readableStreamDefaultControllerShouldCallPull(controller) {
-  const stream = $getByIdDirectPrivate(controller, "controlledReadableStream");
-
   if (!$readableStreamDefaultControllerCanCloseOrEnqueue(controller)) return false;
   if (!($getByIdDirectPrivate(controller, "started") === 1)) return false;
+
+  const stream = $getByIdDirectPrivate(controller, "controlledReadableStream");
+
   if (
     (!$isReadableStreamLocked(stream) ||
       !$getByIdDirectPrivate($getByIdDirectPrivate(stream, "reader"), "readRequests")?.isNotEmpty()) &&
@@ -1482,10 +1483,17 @@ export function readableStreamReaderGenericRelease(reader) {
 }
 
 export function readableStreamDefaultControllerCanCloseOrEnqueue(controller) {
-  return (
-    !$getByIdDirectPrivate(controller, "closeRequested") &&
-    $getByIdDirectPrivate($getByIdDirectPrivate(controller, "controlledReadableStream"), "state") === $streamReadable
-  );
+  if ($getByIdDirectPrivate(controller, "closeRequested")) {
+    return false;
+  }
+
+  const controlledReadableStream = $getByIdDirectPrivate(controller, "controlledReadableStream");
+
+  if (!$isObject(controlledReadableStream)) {
+    return false;
+  }
+
+  return $getByIdDirectPrivate(controlledReadableStream, "state") === $streamReadable;
 }
 
 export function lazyLoadStream(stream, autoAllocateChunkSize) {