Fix undefined is not a function error in WritableStream

2 files changed, 5 insertions, 3 deletions

diff --git a/src/bun.js/builtins/js/StreamInternals.js b/src/bun.js/builtins/js/StreamInternals.js
index 9f8cb84f4..5e8e4a119 100644
--- a/src/bun.js/builtins/js/StreamInternals.js
+++ b/src/bun.js/builtins/js/StreamInternals.js
@@ -252,7 +252,7 @@ function peekQueueValue(queue)
 
     @assert(queue.content.isNotEmpty());
 
-    return queue.peek().value;
+    return queue.peek()?.value;
 }
 
 function resetQueue(queue)
diff --git a/src/bun.js/builtins/js/WritableStreamInternals.js b/src/bun.js/builtins/js/WritableStreamInternals.js
index 5a97155f2..58c4ee87c 100644
--- a/src/bun.js/builtins/js/WritableStreamInternals.js
+++ b/src/bun.js/builtins/js/WritableStreamInternals.js
@@ -714,10 +714,12 @@ function writableStreamDefaultControllerAdvanceQueueIfNeeded(controller)
         return;
     }
 
-    if (@getByIdDirectPrivate(controller, "queue").content?.isEmpty() ?? false)
+    const queue = @getByIdDirectPrivate(controller, "queue");
+
+    if (queue.content?.isEmpty() ?? false)
         return;
 
-    const value = @peekQueueValue(@getByIdDirectPrivate(controller, "queue"));
+    const value = @peekQueueValue(queue);
     if (value === @isCloseSentinel)
         @writableStreamDefaultControllerProcessClose(controller);
     else