streams: more iter streams fixes

[jasnell]

Another batch of iterable streams fixes. See each commit.

[nodejs-github-bot]

Review requested:

• @nodejs/streams

[codecov]

Codecov Report

❌ Patch coverage is 89.06250% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 90.23%. Comparing base (dbfa70a) to head (1c49e7e).
⚠️ Report is 17 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/internal/streams/iter/broadcast.js	87.50%	3 Missing and 1 partial ⚠️
lib/internal/streams/iter/share.js	90.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #66028      +/-   ##
==========================================
- Coverage   92.76%   90.23%   -2.54%     
==========================================
  Files         420      789     +369     
  Lines      189145   270654   +81509     
  Branches    29054    51815   +22761     
==========================================
+ Hits       175460   244219   +68759     
- Misses      13362    16916    +3554     
- Partials      323     9519    +9196     

Files with missing lines	Coverage Δ
lib/internal/quic/quic.js	100.00% <100.00%> (ø)
lib/internal/streams/iter/share.js	89.51% <90.00%> (+1.71%)	⬆️
lib/internal/streams/iter/broadcast.js	90.17% <87.50%> (-0.03%)	⬇️

... and 502 files with indirect coverage changes

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• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
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[panva]

Review Assisted-by: Codex

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/77538/ 💛

[pimterry]

LGTM 👍

Thanks for fixing the QUIC tests here, looks like #65862 and #63967 landed in parallel with conflicting changes, sorry I didn't catch that!

[nodejs-github-bot]

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  ✖  20c2d6eca1f428c5aca85a8856e9026695f562f5
     ✖  0:34     Do not use consecutive spaces in title.   title-format

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Full Commit Queue output

�[36m⠋�[39m Loading data for nodejs/node/pull/66028
�[36m⠋�[39m Loading data for nodejs/node/pull/66028
�[36m⠋�[39m Getting collaborator contacts from README of nodejs/node
�[36m⠋�[39m Getting PR from nodejs/node/pull/66028
�[36m⠋�[39m Getting reviews from nodejs/node/pull/66028
�[36m⠋�[39m Getting comments from nodejs/node/pull/66028
�[36m⠋�[39m Getting commits from nodejs/node/pull/66028
✔  Done loading data for nodejs/node/pull/66028
----------------------------------- PR info ------------------------------------
Title      streams: more iter streams fixes (#66028)
Author     James M Snell <jasnell@gmail.com> (@jasnell)
Branch     jasnell:jasnell/moar-iter-streams -> nodejs:main
Labels     stream, author ready, needs-ci, commit-queue, commit-queue-rebase
Commits    6
 - stream: update broadcast to retain buffered data with zero consumers
 - stream: make Broadcast.from abort its background pump
 - stream: make share budget failures detach before throwing
 - stream: reject unbounded at SyncShare construction
 - stream: fixup stream/iter to drop at most one entry per share call
 - quic: fix timeout regression from  11ed32572b3
Committers 1
 - James M Snell <jasnell@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/66028
Reviewed-By: Filip Skokan <panva.ip@gmail.com>
Reviewed-By: Tim Perry <pimterry@gmail.com>
------------------------------ Generated metadata ------------------------------
PR-URL: https://github.com/nodejs/node/pull/66028
Reviewed-By: Filip Skokan <panva.ip@gmail.com>
Reviewed-By: Tim Perry <pimterry@gmail.com>
--------------------------------------------------------------------------------
   ℹ  This PR was created on Tue, 15 Sep 2026 03:39:54 GMT
   ✔  Approvals: 2
   ✔  - Filip Skokan (@panva) (TSC): https://github.com/nodejs/node/pull/66028#pullrequestreview-5212723553
   ✔  - Tim Perry (@pimterry): https://github.com/nodejs/node/pull/66028#pullrequestreview-5228559103
   ✔  Last GitHub CI successful
   ℹ  Last Full PR CI on 2026-09-16T00:43:54Z: https://ci.nodejs.org/job/node-test-pull-request/77538/
�[36m⠙�[39m Querying data for job/node-test-pull-request/77538/
�[36m⠙�[39m Querying data for job/node-test-pull-request/77538/
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✔  Build data downloaded
   ✔  Last Jenkins CI successful
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   ✔  No git cherry-pick in progress
   ✔  No git am in progress
   ✔  No git rebase in progress
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�[36m⠹�[39m Bringing origin/main up to date...
�[36m⠹�[39m Bringing origin/main up to date...
From https://github.com/nodejs/node
 * branch                  main       -> FETCH_HEAD
✔  origin/main is now up-to-date
�[36m⠸�[39m Downloading patch for 66028
�[36m⠸�[39m Downloading patch for 66028
From https://github.com/nodejs/node
 * branch                  refs/pull/66028/merge -> FETCH_HEAD
✔  Fetched commits as edc61b14de8e..1c49e7ed7f55
--------------------------------------------------------------------------------
[main d9b14f44cd] stream: update broadcast to retain buffered data with zero consumers
 Author: James M Snell <jasnell@gmail.com>
 Date: Sun Aug 30 14:44:24 2026 +0000
 2 files changed, 15 insertions(+)
[main 032e583ea7] stream: make Broadcast.from abort its background pump
 Author: James M Snell <jasnell@gmail.com>
 Date: Sun Aug 30 15:03:26 2026 +0000
 2 files changed, 68 insertions(+), 29 deletions(-)
[main fe3e98af70] stream: make share budget failures detach before throwing
 Author: James M Snell <jasnell@gmail.com>
 Date: Sun Aug 30 15:09:17 2026 +0000
 2 files changed, 31 insertions(+), 16 deletions(-)
[main 2453e38842] stream: reject unbounded at SyncShare construction
 Author: James M Snell <jasnell@gmail.com>
 Date: Sun Aug 30 15:18:58 2026 +0000
 2 files changed, 50 insertions(+), 10 deletions(-)
[main 35a3bb9217] stream: fixup stream/iter to drop at most one entry per share call
 Author: James M Snell <jasnell@gmail.com>
 Date: Tue Sep 15 16:15:27 2026 +0000
 3 files changed, 63 insertions(+), 11 deletions(-)
[main 8eb8e5b622] quic: fix timeout regression from  11ed32572b3
 Author: James M Snell <jasnell@gmail.com>
 Date: Tue Sep 15 20:36:29 2026 +0000
 1 file changed, 2 insertions(+), 7 deletions(-)
   ✔  Patches applied
There are 6 commits in the PR. Attempting autorebase.
(node:695) [DEP0190] DeprecationWarning: Passing args to a child process with shell option true can lead to security vulnerabilities, as the arguments are not escaped, only concatenated.
(Use `node --trace-deprecation ...` to show where the warning was created)
Rebasing (2/12)
Executing: git node land --amend --yes
--------------------------------- New Message ----------------------------------
stream: update broadcast to retain buffered data with zero consumers

While the Broadcast is still open, maintain buffered data when
consumer count reaches zero

Signed-off-by: James M Snell <jasnell@gmail.com>
Assisted-by: Opencode
PR-URL: https://github.com/nodejs/node/pull/66028
Reviewed-By: Filip Skokan <panva.ip@gmail.com>
Reviewed-By: Tim Perry <pimterry@gmail.com>
--------------------------------------------------------------------------------
[detached HEAD dd660cc909] stream: update broadcast to retain buffered data with zero consumers
 Author: James M Snell <jasnell@gmail.com>
 Date: Sun Aug 30 14:44:24 2026 +0000
 2 files changed, 15 insertions(+)
Rebasing (3/12)
Rebasing (4/12)
Executing: git node land --amend --yes
--------------------------------- New Message ----------------------------------
stream: make Broadcast.from abort its background pump

Signed-off-by: James M Snell <jasnell@gmail.com>
Assisted-by: Opencode
PR-URL: https://github.com/nodejs/node/pull/66028
Reviewed-By: Filip Skokan <panva.ip@gmail.com>
Reviewed-By: Tim Perry <pimterry@gmail.com>
--------------------------------------------------------------------------------
[detached HEAD 260ea504f2] stream: make Broadcast.from abort its background pump
 Author: James M Snell <jasnell@gmail.com>
 Date: Sun Aug 30 15:03:26 2026 +0000
 2 files changed, 68 insertions(+), 29 deletions(-)
Rebasing (5/12)
Rebasing (6/12)
Executing: git node land --amend --yes
--------------------------------- New Message ----------------------------------
stream: make share budget failures detach before throwing

Signed-off-by: James M Snell <jasnell@gmail.com>
Assisted-by: Opencode
PR-URL: https://github.com/nodejs/node/pull/66028
Reviewed-By: Filip Skokan <panva.ip@gmail.com>
Reviewed-By: Tim Perry <pimterry@gmail.com>
--------------------------------------------------------------------------------
[detached HEAD ed0a62649d] stream: make share budget failures detach before throwing
 Author: James M Snell <jasnell@gmail.com>
 Date: Sun Aug 30 15:09:17 2026 +0000
 2 files changed, 31 insertions(+), 16 deletions(-)
Rebasing (7/12)
Rebasing (8/12)
Executing: git node land --amend --yes
--------------------------------- New Message ----------------------------------
stream: reject unbounded at SyncShare construction

Signed-off-by: James M Snell <jasnell@gmail.com>
Assisted-by: Opencode
PR-URL: https://github.com/nodejs/node/pull/66028
Reviewed-By: Filip Skokan <panva.ip@gmail.com>
Reviewed-By: Tim Perry <pimterry@gmail.com>
--------------------------------------------------------------------------------
[detached HEAD 9c2b36dd6e] stream: reject unbounded at SyncShare construction
 Author: James M Snell <jasnell@gmail.com>
 Date: Sun Aug 30 15:18:58 2026 +0000
 2 files changed, 50 insertions(+), 10 deletions(-)
Rebasing (9/12)
Rebasing (10/12)
Executing: git node land --amend --yes
--------------------------------- New Message ----------------------------------
stream: fixup stream/iter to drop at most one entry per share call

Signed-off-by: James M Snell <jasnell@gmail.com>
Assisted-by: Opencode
PR-URL: https://github.com/nodejs/node/pull/66028
Reviewed-By: Filip Skokan <panva.ip@gmail.com>
Reviewed-By: Tim Perry <pimterry@gmail.com>
--------------------------------------------------------------------------------
[detached HEAD 9fa2d5c7b8] stream: fixup stream/iter to drop at most one entry per share call
 Author: James M Snell <jasnell@gmail.com>
 Date: Tue Sep 15 16:15:27 2026 +0000
 3 files changed, 63 insertions(+), 11 deletions(-)
Rebasing (11/12)
Rebasing (12/12)
Executing: git node land --amend --yes
--------------------------------- New Message ----------------------------------
quic: fix timeout regression from  11ed32572b3

Commit 11ed32572b3 introduced a regression in quic

Signed-off-by: James M Snell <jasnell@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/66028
Reviewed-By: Filip Skokan <panva.ip@gmail.com>
Reviewed-By: Tim Perry <pimterry@gmail.com>
--------------------------------------------------------------------------------
[detached HEAD 20c2d6eca1] quic: fix timeout regression from  11ed32572b3
 Author: James M Snell <jasnell@gmail.com>
 Date: Tue Sep 15 20:36:29 2026 +0000
 1 file changed, 2 insertions(+), 7 deletions(-)
Successfully rebased and updated refs/heads/main.
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[jasnell]

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