stream: abort pending single-source merge reads by trivikr · Pull Request #64445 · nodejs/node

trivikr · 2026-07-12T05:22:00Z

The single-source merge() path uses a plain for await loop, so aborting
during a pending read neither rejects next() nor closes the source iterator.

Make the single-source path abort-aware before normalization so cancellation
reaches the active source iterator. Also allow the shared abort cleanup helper
to handle iterators whose return() method returns a synchronous iterator
result.

nodejs-github-bot · 2026-07-12T05:22:06Z

Review requested:

@nodejs/streams

codecov · 2026-07-12T07:00:28Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (3437feb) to head (5a03b0f).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #64445 +/- ##
=======================================
Coverage 90.13% 90.13% =======================================
Files 741 741 Lines 242158 242163 +5 Branches 45608 45609 +1 =======================================
+ Hits 218265 218277 +12 - Misses 15361 15385 +24 + Partials 8532 8501 -31

Files with missing lines	Coverage Δ
lib/internal/streams/iter/consumers.js	`96.64% <100.00%> (+0.01%)`	⬆️
lib/internal/streams/iter/utils.js	`98.23% <100.00%> (+0.01%)`	⬆️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

mcollina

lgtm

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com>

nodejs-github-bot · 2026-07-23T23:28:15Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75079/

nodejs-github-bot · 2026-07-24T05:08:11Z

Landed in 7bee754

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com> PR-URL: #64445Fixes: #64444 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Ethan Arrowood <ethan@arrowood.dev>

trivikr · 2026-07-12T05:22:00Z

Fixes: #64444

The single-source merge() path uses a plain for await loop, so aborting
during a pending read neither rejects next() nor closes the source iterator.

Make the single-source path abort-aware before normalization so cancellation
reaches the active source iterator. Also allow the shared abort cleanup helper
to handle iterators whose return() method returns a synchronous iterator
result.

nodejs-github-bot · 2026-07-12T05:22:06Z

Review requested:

@nodejs/streams

codecov · 2026-07-12T07:00:28Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (3437feb) to head (5a03b0f).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #64445 +/- ##
=======================================
Coverage 90.13% 90.13% =======================================
Files 741 741 Lines 242158 242163 +5 Branches 45608 45609 +1 =======================================
+ Hits 218265 218277 +12 - Misses 15361 15385 +24 + Partials 8532 8501 -31

Files with missing lines	Coverage Δ
lib/internal/streams/iter/consumers.js	`96.64% <100.00%> (+0.01%)`	⬆️
lib/internal/streams/iter/utils.js	`98.23% <100.00%> (+0.01%)`	⬆️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

mcollina

lgtm

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com>

nodejs-github-bot · 2026-07-23T23:28:15Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75079/

nodejs-github-bot · 2026-07-24T05:08:11Z

Landed in 7bee754

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com> PR-URL: #64445Fixes: #64444 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Ethan Arrowood <ethan@arrowood.dev>

trivikr · 2026-07-12T05:22:00Z

Fixes: #64444

The single-source merge() path uses a plain for await loop, so aborting
during a pending read neither rejects next() nor closes the source iterator.

Make the single-source path abort-aware before normalization so cancellation
reaches the active source iterator. Also allow the shared abort cleanup helper
to handle iterators whose return() method returns a synchronous iterator
result.

nodejs-github-bot · 2026-07-12T05:22:06Z

Review requested:

@nodejs/streams

codecov · 2026-07-12T07:00:28Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (3437feb) to head (5a03b0f).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #64445 +/- ##
=======================================
Coverage 90.13% 90.13% =======================================
Files 741 741 Lines 242158 242163 +5 Branches 45608 45609 +1 =======================================
+ Hits 218265 218277 +12 - Misses 15361 15385 +24 + Partials 8532 8501 -31

Files with missing lines	Coverage Δ
lib/internal/streams/iter/consumers.js	`96.64% <100.00%> (+0.01%)`	⬆️
lib/internal/streams/iter/utils.js	`98.23% <100.00%> (+0.01%)`	⬆️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

mcollina

lgtm

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com>

nodejs-github-bot · 2026-07-23T23:28:15Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75079/

nodejs-github-bot · 2026-07-24T05:08:11Z

Landed in 7bee754

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com> PR-URL: #64445Fixes: #64444 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Ethan Arrowood <ethan@arrowood.dev>

trivikr · 2026-07-12T05:22:00Z

Fixes: #64444

The single-source merge() path uses a plain for await loop, so aborting
during a pending read neither rejects next() nor closes the source iterator.

Make the single-source path abort-aware before normalization so cancellation
reaches the active source iterator. Also allow the shared abort cleanup helper
to handle iterators whose return() method returns a synchronous iterator
result.

nodejs-github-bot · 2026-07-12T05:22:06Z

Review requested:

@nodejs/streams

codecov · 2026-07-12T07:00:28Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (3437feb) to head (5a03b0f).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #64445 +/- ##
=======================================
Coverage 90.13% 90.13% =======================================
Files 741 741 Lines 242158 242163 +5 Branches 45608 45609 +1 =======================================
+ Hits 218265 218277 +12 - Misses 15361 15385 +24 + Partials 8532 8501 -31

Files with missing lines	Coverage Δ
lib/internal/streams/iter/consumers.js	`96.64% <100.00%> (+0.01%)`	⬆️
lib/internal/streams/iter/utils.js	`98.23% <100.00%> (+0.01%)`	⬆️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

mcollina

lgtm

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com>

nodejs-github-bot · 2026-07-23T23:28:15Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75079/

nodejs-github-bot · 2026-07-24T05:08:11Z

Landed in 7bee754

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com> PR-URL: #64445Fixes: #64444 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Ethan Arrowood <ethan@arrowood.dev>

trivikr · 2026-07-12T05:22:00Z

Fixes: #64444

The single-source merge() path uses a plain for await loop, so aborting
during a pending read neither rejects next() nor closes the source iterator.

Make the single-source path abort-aware before normalization so cancellation
reaches the active source iterator. Also allow the shared abort cleanup helper
to handle iterators whose return() method returns a synchronous iterator
result.

nodejs-github-bot · 2026-07-12T05:22:06Z

Review requested:

@nodejs/streams

codecov · 2026-07-12T07:00:28Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (3437feb) to head (5a03b0f).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #64445 +/- ##
=======================================
Coverage 90.13% 90.13% =======================================
Files 741 741 Lines 242158 242163 +5 Branches 45608 45609 +1 =======================================
+ Hits 218265 218277 +12 - Misses 15361 15385 +24 + Partials 8532 8501 -31

Files with missing lines	Coverage Δ
lib/internal/streams/iter/consumers.js	`96.64% <100.00%> (+0.01%)`	⬆️
lib/internal/streams/iter/utils.js	`98.23% <100.00%> (+0.01%)`	⬆️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

mcollina

lgtm

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com>

nodejs-github-bot · 2026-07-23T23:28:15Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75079/

nodejs-github-bot · 2026-07-24T05:08:11Z

Landed in 7bee754

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com> PR-URL: #64445Fixes: #64444 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Ethan Arrowood <ethan@arrowood.dev>

trivikr · 2026-07-12T05:22:00Z

Fixes: #64444

The single-source merge() path uses a plain for await loop, so aborting
during a pending read neither rejects next() nor closes the source iterator.

Make the single-source path abort-aware before normalization so cancellation
reaches the active source iterator. Also allow the shared abort cleanup helper
to handle iterators whose return() method returns a synchronous iterator
result.

nodejs-github-bot · 2026-07-12T05:22:06Z

Review requested:

@nodejs/streams

codecov · 2026-07-12T07:00:28Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (3437feb) to head (5a03b0f).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #64445 +/- ##
=======================================
Coverage 90.13% 90.13% =======================================
Files 741 741 Lines 242158 242163 +5 Branches 45608 45609 +1 =======================================
+ Hits 218265 218277 +12 - Misses 15361 15385 +24 + Partials 8532 8501 -31

Files with missing lines	Coverage Δ
lib/internal/streams/iter/consumers.js	`96.64% <100.00%> (+0.01%)`	⬆️
lib/internal/streams/iter/utils.js	`98.23% <100.00%> (+0.01%)`	⬆️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

mcollina

lgtm

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com>

nodejs-github-bot · 2026-07-23T23:28:15Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75079/

nodejs-github-bot · 2026-07-24T05:08:11Z

Landed in 7bee754

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com> PR-URL: #64445Fixes: #64444 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Ethan Arrowood <ethan@arrowood.dev>

trivikr · 2026-07-12T05:22:00Z

Fixes: #64444

The single-source merge() path uses a plain for await loop, so aborting
during a pending read neither rejects next() nor closes the source iterator.

Make the single-source path abort-aware before normalization so cancellation
reaches the active source iterator. Also allow the shared abort cleanup helper
to handle iterators whose return() method returns a synchronous iterator
result.

nodejs-github-bot · 2026-07-12T05:22:06Z

Review requested:

@nodejs/streams

codecov · 2026-07-12T07:00:28Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (3437feb) to head (5a03b0f).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #64445 +/- ##
=======================================
Coverage 90.13% 90.13% =======================================
Files 741 741 Lines 242158 242163 +5 Branches 45608 45609 +1 =======================================
+ Hits 218265 218277 +12 - Misses 15361 15385 +24 + Partials 8532 8501 -31

Files with missing lines	Coverage Δ
lib/internal/streams/iter/consumers.js	`96.64% <100.00%> (+0.01%)`	⬆️
lib/internal/streams/iter/utils.js	`98.23% <100.00%> (+0.01%)`	⬆️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

mcollina

lgtm

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com>

nodejs-github-bot · 2026-07-23T23:28:15Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75079/

nodejs-github-bot · 2026-07-24T05:08:11Z

Landed in 7bee754

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com> PR-URL: #64445Fixes: #64444 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Ethan Arrowood <ethan@arrowood.dev>

trivikr · 2026-07-12T05:22:00Z

Fixes: #64444

The single-source merge() path uses a plain for await loop, so aborting
during a pending read neither rejects next() nor closes the source iterator.

Make the single-source path abort-aware before normalization so cancellation
reaches the active source iterator. Also allow the shared abort cleanup helper
to handle iterators whose return() method returns a synchronous iterator
result.

nodejs-github-bot · 2026-07-12T05:22:06Z

Review requested:

@nodejs/streams

codecov · 2026-07-12T07:00:28Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (3437feb) to head (5a03b0f).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #64445 +/- ##
=======================================
Coverage 90.13% 90.13% =======================================
Files 741 741 Lines 242158 242163 +5 Branches 45608 45609 +1 =======================================
+ Hits 218265 218277 +12 - Misses 15361 15385 +24 + Partials 8532 8501 -31

Files with missing lines	Coverage Δ
lib/internal/streams/iter/consumers.js	`96.64% <100.00%> (+0.01%)`	⬆️
lib/internal/streams/iter/utils.js	`98.23% <100.00%> (+0.01%)`	⬆️

... and 31 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

mcollina

lgtm

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com>

nodejs-github-bot · 2026-07-23T23:28:15Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75079/

nodejs-github-bot · 2026-07-24T05:08:11Z

Landed in 7bee754

Make the single-source merge path abort-aware so signal cancellation rejects a pending read and closes the active source iterator. Handle synchronous iterator return values when marking aborted cleanup as handled. Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com> PR-URL: #64445Fixes: #64444 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Ethan Arrowood <ethan@arrowood.dev>

nodejs-github-bot added needs-ci PRs that need a full CI run. stream Issues and PRs related to Node.js streams. labels Jul 12, 2026

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jasnell reviewed Jul 12, 2026
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Comment threadlib/internal/streams/iter/utils.js

jasnell reviewed Jul 12, 2026
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Comment threadtest/parallel/test-stream-iter-consumers-merge.js

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trivikr force-pushed the stream-iter-single-source-merge-abort-pending-read branch from 5fac436 to 1ee6017Compare July 12, 2026 20:22

trivikr marked this pull request as draft July 22, 2026 05:19

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trivikr marked this pull request as ready for review July 23, 2026 13:04

trivikr added 3 commits July 23, 2026 06:06

fixup! stream: explain handling of rejecting iterator return thenables
93cad7b

fixup! test: explain intentionally pending promise in stream merge test
5a03b0f

trivikr force-pushed the stream-iter-single-source-merge-abort-pending-read branch from 1ee6017 to 5a03b0fCompare July 23, 2026 13:06

trivikr requested a review from jasnell July 23, 2026 13:06

jasnell approved these changes Jul 23, 2026
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Ethan-Arrowood approved these changes Jul 23, 2026
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trivikr added commit-queue-squash PRs the Commit Queue should land as one squashed commit. commit-queue PRs queued for automated landing through the Commit Queue. labels Jul 24, 2026

nodejs-github-bot removed the commit-queue PRs queued for automated landing through the Commit Queue. label Jul 24, 2026

nodejs-github-bot merged commit 7bee754 into nodejs:mainJul 24, 2026
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aduh95 mentioned this pull request Jul 30, 2026
2026-07-22, Version 26.6.0 (Current) #64655
Merged

trivikr deleted the stream-iter-single-source-merge-abort-pending-read branch July 31, 2026 04:30

github-actionsBot mentioned this pull request Aug 21, 2026
2026-08-26, Version 24.20.0 'Krypton' (LTS) #65461
Merged