sync: return TryRecvError::Disconnected from Receiver::try_recv after Receiver::close#7686
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Darksonn merged 6 commits intotokio-rs:masterfrom Oct 18, 2025
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Co-authored-by: Alice Ryhl <aliceryhl@google.com>
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Can you update documentation for TryPopResult::Empty in tokio/src/sync/mpsc/list.rs to mention that it might be closed.
In fact, maybe Empty should be renamed?
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Or maybe Closed should be renamed to ClosedBySender?
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I think a docs-only update would be the best approach for now:
- Document that
TryPopResult::Emptycan be returned afterRx::close()when the queue is empty (even if senders still exist) - Clarify in the docs that
TryPopResult::Closedspecifically means the send half closed (all senders dropped, no further items will be produced)
I'd prefer to defer renaming the variants in this PR. My concern is that if we rename now and discover additional edge cases later, we might need to rename again, which could cause unnecessary churn.
That said, I'm open to including the rename if you feel strongly about it—just wanted to share my reasoning. Would this documentation approach work for you?
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Superseded by this inline note: https://github.com/tokio-rs/tokio/pull/7686/files/e4347422b990294fbfe7e3e562121094c7eec776#r2433202379
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Docs updated per discussion at this line. If you prefer different wording, I can adjust anytime.
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Co-authored-by: Alice Ryhl <aliceryhl@google.com>
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TryRecvError::Disconnected from Receiver::try_recv after Receiver::close
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…fter `Receiver::close` (tokio-rs#7686) (cherry picked from commit d060401)
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Bumps tokio from 1.48.0 to 1.49.0.
Release notes
Sourced from tokio's releases.
Tokio v1.49.0
1.49.0 (January 3rd, 2026)
Added
net: add support for TCLASS option on IPv6 (#7781)
runtime: stabilize runtime::id::Id (#7125)
task: implement Extend for JoinSet (#7195)
task: stabilize the LocalSet::id() (#7776)
Changed
net: deprecate {TcpStream,TcpSocket}::set_linger (#7752)
Fixed
macros: fix the hygiene issue of join! and try_join! (#7766)
runtime: revert "replace manual vtable definitions with Wake" (#7699)
sync: return TryRecvError::Disconnected from Receiver::try_recv after Receiver::close (#7686)
task: remove unnecessary trait bounds on the Debug implementation (#7720)
Unstable
fs: handle EINTR in fs::write for io-uring (#7786)
fs: support io-uring with tokio::fs::read (#7696)
runtime: disable io-uring on EPERM (#7724)
time: add alternative timer for better multicore scalability (#7467)
Documented
docs: fix a typos in bounded.rs and park.rs (#7817)
io: add SyncIoBridge cross-references to copy and copy_buf (#7798)
io: doc that AsyncWrite does not inherit from std::io::Write (#7705)
metrics: clarify that num_alive_tasks is not strongly consistent (#7614)
net: clarify the cancellation safety of the TcpStream::peek (#7305)
net: clarify the drop behavior of unix::OwnedWriteHalf (#7742)
net: clarify the platform-dependent backlog in TcpSocket docs (#7738)
runtime: mention LocalRuntime in new_current_thread docs (#7820)
sync: add missing period to mpsc::Sender::try_send docs (#7721)
sync: clarify the cancellation safety of oneshot::Receiver (#7780)
sync: improve the docs for the errors of mpsc (#7722)
task: add example for spawn_local usage on local runtime (#7689)
#7125: tokio-rs/tokio#7125
#7195: tokio-rs/tokio#7195
#7305: tokio-rs/tokio#7305
#7467: tokio-rs/tokio#7467
#7614: tokio-rs/tokio#7614
#7686: tokio-rs/tokio#7686
#7689: tokio-rs/tokio#7689
... (truncated)
Commits
e3b89bb chore: prepare Tokio v1.49.0 (#7824)
4f577b8 Merge 'tokio-1.47.3' into 'master'
f320197 chore: prepare Tokio v1.47.3 (#7823)
ea6b144 ci: freeze rustc on nightly-2025-01-25 in netlify.toml (#7652)
264e703 Merge tokio-1.43.4 into tokio-1.47.x (#7822)
dfb0f00 chore: prepare Tokio v1.43.4 (#7821)
4a91f19 ci: fix wasm32-wasip1 tests (#7788)
601c383 ci: upgrade FreeBSD from 14.2 to 14.3 (#7758)
484cb52 sync: return TryRecvError::Disconnected from Receiver::try_recv after `Re...
16f20c3 rt: mention LocalRuntime in new_current_thread docs (#7820)
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Closes #7631
Motivation
After calling
Receiver::close, a follow-uptry_recvshould returnTryRecvError::Disconnected, but it currently yieldsTryRecvError::Empty.Solution
Update
Rx::try_recvso that when it hitsTryPopResult::Emptyand the receiver has been closed, it now returnsTryRecvError::Disconnectedinstead ofEmpty.