Sandbox::https://github.com/aio-libs/aiohttp/pull/14327

0718lol · 2026-11-09T00:49:01Z

What do these changes do?

Fix direct stream writes of C-contiguous memoryviews. write() now checks dimensions and element size without calling len() on scalar views. write_eof() performs the same byte-view normalization before framing or transport writes, and uses nbytes for progress accounting. Empty multidimensional views become an empty chunk without attempting an invalid cast.

For example, an 8-byte view cast to H previously produced a final HTTP chunk advertised as 4 bytes, which the client rejected. It now produces an 8-byte chunk containing the original bytes. Scalar views no longer raise TypeError.

Are there changes in behavior for the user?

Direct StreamResponse writes send the raw buffer bytes independently of element size and shape. The writer preserves the original view for the chunk callback, and casts nonempty contiguous views without copying. This is separate from #14019's BytesPayload change: the new HTTP tests use StreamResponse directly.

Is it a substantial burden for the maintainers to support this?

The change extends the existing normalization in the writer to its final-chunk path, with focused regressions and a short reference-doc update. It adds no dependency or public API.

Related issue number

Fixes #14326.

Checklist

I think the code is well written
Unit tests for the changes exist
Documentation reflects the changes
Added the contributor handle 0718lol to CONTRIBUTORS.txt in sorted order (the account has no public full name).
Added a news fragment under CHANGES/.

Local validation

Base: 8f51d5be21bbd021160079d9d6dae739814bd0cf. macOS arm64, CPython 3.12.15, pure Python mode.

The same 38 regression cases produced 19 failures / 19 passes with baseline production code and 38 passes with the fix. They cover chunk framing with buffered and unbuffered headers, output/progress byte counts, callback inputs, byte limits, and 12 real HTTP round trips with and without compression.

AIOHTTP_NO_EXTENSIONS=1 python -X dev -m pytest -p no:aiohttp -o addopts='' \
  -m 'not autobahn and not internal' \
  tests/test_http_writer.py tests/test_client_functional.py \
  tests/test_web_response.py tests/test_payload.py tests/test_client_request.py \
  -q --tb=short --timeout=15
994 passed, 71 skipped, 11 deselected, 1 xfailed

mypy --follow-imports=silent aiohttp/http_writer.py \
  tests/test_http_writer.py tests/test_client_functional.py
Success: no issues found in 3 source files

All applicable repository pre-commit hooks passed, as did git diff --check. The full repository suite, other interpreters, and compiled extensions were not run. No parser or WebSocket code changes are included.

Drafted with OpenAI Codex (GPT-6); human review by 0718lol pending. This PR remains a draft until that review occurs, as required by AGENTS.md.

agentscanapp · 2026-11-09T00:49:06Z

Automation signals

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Evidence

Multiple forks: 7 repositories forked in a single 24-hour window
Issue comment and PR within minutes: Commented on an issue and opened a PR to the same repo within 5 minutes, in 2 repositories (the fastest took 1s)

Last 2 PRs:

_{This is an automated analysis by AgentScan}

codecov · 2026-11-09T00:52:54Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.11%. Comparing base (8f51d5b) to head (e3c6d19).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #14327   +/-   ##
=======================================
  Coverage   99.11%   99.11%           
=======================================
  Files         135      135           
  Lines       53439    53494   +55     
  Branches     2723     2728    +5     
=======================================
+ Hits        52967    53022   +55     
  Misses        358      358           
  Partials      114      114

Flag	Coverage Δ
Autobahn	`21.67% <19.67%> (-0.01%)`	⬇️
CI-GHA	`99.05% <100.00%> (+<0.01%)`	⬆️
OS-Linux	`98.69% <100.00%> (+<0.01%)`	⬆️
OS-Windows	`97.48% <100.00%> (-0.01%)`	⬇️
OS-macOS	`98.35% <100.00%> (+<0.01%)`	⬆️
Py-3.11	`98.29% <100.00%> (-0.01%)`	⬇️
Py-3.12	`98.38% <100.00%> (+<0.01%)`	⬆️
Py-3.13	`98.36% <100.00%> (+<0.01%)`	⬆️
Py-3.14	`98.40% <100.00%> (+<0.01%)`	⬆️
Py-3.15	`98.39% <100.00%> (+<0.01%)`	⬆️
Py-3.15t	`98.24% <100.00%> (+<0.01%)`	⬆️
Py-pypy-3.12	`96.96% <100.00%> (+0.01%)`	⬆️
VM-macos-latest	`98.35% <100.00%> (+<0.01%)`	⬆️
VM-ubuntu-latest	`98.69% <100.00%> (+<0.01%)`	⬆️
VM-windows-latest	`97.48% <100.00%> (-0.01%)`	⬇️
cython-coverage	`83.84% <100.00%> (+0.03%)`	⬆️

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codspeed · 2026-11-09T01:01:43Z

Merging this PR will not alter performance

1 warning

⚠️ 48 benchmarks are dominated by system calls

System calls cannot be simulated consistently and are left out of the measure. The reported value understates the real cost. Switch to the Walltime instrument to measure them.

Learn more about system calls

See affected benchmarks

✅ 102 untouched benchmarks
⏩ 83 skipped benchmarks¹

_{Comparing 0718lol:fix/stream-memoryview-byte-length (e3c6d19) with master (8f51d5b)}

83 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

0718lol · 2026-11-09T04:21:23Z

CI is now passing except for “Backport label added”. The affected code exists in both 3.14 and 3.15. Could a maintainer add the appropriate backport labels? I don’t have permission to set upstream labels.

Fix byte-length handling for stream memoryviews

01d0eb6

pyba-chronographer Bot added the bot:chronographer:provided There is a change note present in this PR label Nov 9, 2026

agentscanapp Bot added the agentscan:automation-signals label Nov 9, 2026

github-actions Bot added the agentscan:automated-account label Nov 9, 2026

Link the news fragment to PR 14327

aee30e5

Allow the memoryviews term in documentation spelling

e3c6d19

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Fix byte-length handling for stream memoryviews - #14327

Fix byte-length handling for stream memoryviews#14327
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0718lol commented Nov 9, 2026

What do these changes do?

Are there changes in behavior for the user?

Is it a substantial burden for the maintainers to support this?

Related issue number

Checklist

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Automation signals

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