From bb9515457ea73f032e69169d3a620cfc713f9955 Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Thu, 3 Apr 2025 11:20:22 -0700
Subject: [PATCH] Fix `StreamWriter::write_all` wrt
 WebAssembly/component-model#490

Handle the fact that cancellation/0-length writes look the same.
---
 crates/guest-rust/rt/src/async_support/stream_support.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/crates/guest-rust/rt/src/async_support/stream_support.rs b/crates/guest-rust/rt/src/async_support/stream_support.rs
index 2b0fd26dd..7e07344e6 100644
--- a/crates/guest-rust/rt/src/async_support/stream_support.rs
+++ b/crates/guest-rust/rt/src/async_support/stream_support.rs
@@ -160,6 +160,11 @@ impl<T> StreamWriter<T> {
                 break;
             }
             (status, buf) = self.write_buf(buf).await;
+
+            // FIXME(WebAssembly/component-model#490)
+            if status == StreamResult::Cancelled {
+                status = StreamResult::Complete(0);
+            }
         }
 
         // Return back any values that weren't written by shifting them to the