From 763e6f46e06d05bc23148d1c05b9516a6f02b1ba Mon Sep 17 00:00:00 2001
From: Jiahao XU <30436523+NobodyXu@users.noreply.github.com>
Date: Mon, 3 Nov 2025 13:54:38 +0000
Subject: [PATCH] Early return in `do_poll_read` instead of keep polling

if there're some data already written to
`output`, so that the next component in pipeline
can process it instead of being blocked.
---
 crates/async-compression/src/generic/bufread/encoder.rs | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/crates/async-compression/src/generic/bufread/encoder.rs b/crates/async-compression/src/generic/bufread/encoder.rs
index 4187c9b7..e6fe4b07 100644
--- a/crates/async-compression/src/generic/bufread/encoder.rs
+++ b/crates/async-compression/src/generic/bufread/encoder.rs
@@ -35,9 +35,12 @@ impl Encoder {
                 State::Encoding(mut read) => match input.as_mut() {
                     None => {
                         if read == 0 {
-                            // Poll for more data
-                            // TODO (nobodyxu): Return Ok if `!output.written().is_empty()`
-                            break;
+                            if output.written().is_empty() {
+                                // Poll for more data
+                                break;
+                            } else {
+                                return ControlFlow::Break(Ok(()));
+                            }
                         } else {
                             State::Flushing
                         }