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hugovk merged 5 commits into from
Jan 11, 2026
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gh-143420: Clarify sequence behavior for slice indexes #143422

hugovk merged 5 commits into from
Jan 11, 2026

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@skirpichev skirpichev commented Jan 5, 2026 •
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This explain what happens when for negative start or stop arguments of big magnitude.

Also reference sequence term in the :mod:array docs.

📚 Documentation preview 📚: https://cpython-previews--143422.org.readthedocs.build/en/143422/library/stdtypes.html

https://cpython-previews--143422.org.readthedocs.build/en/143422/library/stdtypes.html#common-sequence-operations

@skirpichev
pythongh-143420: Clarify sequence behavior for slice indexes
598ea16 
This explain what happens when for negative start or stop
arguments of big magnitude.

Also reference sequence term in the :mod:`array` docs.
@skirpichev skirpichev added needs backport to 3.13 bugs and security fixes needs backport to 3.14 bugs and security fixes labels Jan 5, 2026
@bedevere-app bedevere-app bot mentioned this pull request Jan 5, 2026
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@github-project-automation github-project-automation bot moved this to Todo in Docs PRs Jan 5, 2026
@skirpichev skirpichev requested a review from hugovk January 9, 2026 22:54
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skirpichev commented Jan 9, 2026

CC @hugovk, per experts index (see issue thread on proposal to remove redundant methods from array docs)

picnixz
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@skirpichev skirpichev requested a review from picnixz January 10, 2026 23:22
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skirpichev commented Jan 10, 2026

What we should do with common array methods? I think removal (like for other sequence types, e.g. bytearray) is a good idea. But broken links is a problem.

@hugovk hugovk merged commit 23b9377 into python:main Jan 11, 2026
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Thanks @skirpichev for the PR, and @hugovk for merging it 🌮🎉.. I'm working now to backport this PR to: 3.13, 3.14.
🐍🍒⛏🤖

@github-project-automation github-project-automation bot moved this from Todo to Done in Docs PRs Jan 11, 2026
miss-islington pushed a commit to miss-islington/cpython that referenced this pull request Jan 11, 2026
@skirpichev @miss-islington
pythongh-143420: Clarify sequence behavior for slice indexes (pythonG…
75f9eb4 
…H-143422)

(cherry picked from commit 23b9377)

Co-authored-by: Sergey B Kirpichev <skirpichev@gmail.com>
miss-islington pushed a commit to miss-islington/cpython that referenced this pull request Jan 11, 2026
@skirpichev @miss-islington
pythongh-143420: Clarify sequence behavior for slice indexes (pythonG…
060c90e 
…H-143422)

(cherry picked from commit 23b9377)

Co-authored-by: Sergey B Kirpichev <skirpichev@gmail.com>
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GH-143701 is a backport of this pull request to the 3.14 branch.

@bedevere-app bedevere-app bot removed the needs backport to 3.14 bugs and security fixes label Jan 11, 2026
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GH-143703 is a backport of this pull request to the 3.13 branch.

@bedevere-app bedevere-app bot removed the needs backport to 3.13 bugs and security fixes label Jan 11, 2026
hugovk pushed a commit that referenced this pull request Jan 11, 2026
@miss-islington @skirpichev
[3.14] gh-143420: Clarify sequence behavior for slice indexes (GH-143422
1b38e89 
) (#143701)

Co-authored-by: Sergey B Kirpichev <skirpichev@gmail.com>
hugovk pushed a commit that referenced this pull request Jan 11, 2026
@miss-islington @skirpichev
[3.13] gh-143420: Clarify sequence behavior for slice indexes (GH-143422
cf5b31c 
) (#143703)

Co-authored-by: Sergey B Kirpichev <skirpichev@gmail.com>
@skirpichev skirpichev deleted the improve-slice-notes/143420 branch January 11, 2026 18:03
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bedevere-bot commented Jan 11, 2026

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 FreeBSD Refleaks 3.14 (tier-3) has failed when building commit 1b38e89.

What do you need to do:

  1. Don't panic.
  2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
  3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1800/builds/892) and take a look at the build logs.
  4. Check if the failure is related to this commit (1b38e89) or if it is a false positive.
  5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1800/builds/892

Failed tests:

  • test_httpservers
  • test_datetime

Failed subtests:

  • test_large_content_length_truncated - test.test_httpservers.CGIHTTPServerTestCase.test_large_content_length_truncated
  • test_concurrent_initialization_subinterpreter - test.datetimetester.ExtensionModuleTests_Fast.test_concurrent_initialization_subinterpreter

Summary of the results of the build (if available):

==

Click to see traceback logs 
Traceback (most recent call last):
  File "/buildbot/buildarea/3.14.ware-freebsd.refleak/build/Lib/test/datetimetester.py", line 7302, in test_concurrent_initialization_subinterpreter
    self.assertEqual(out, b"a" * 8)
    ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^
AssertionError: b'aaaaaaa' != b'aaaaaaaa'


Traceback (most recent call last):
  File "/buildbot/buildarea/3.14.ware-freebsd.refleak/build/Lib/test/libregrtest/single.py", line 236, in _runtest_env_changed_exc
    return
ResourceWarning: unclosed <socket.socket fd=4, family=2, type=1, proto=6, laddr=('127.0.0.1', 31246)>


Traceback (most recent call last):
  File "/buildbot/buildarea/3.14.ware-freebsd.refleak/build/Lib/test/test_httpservers.py", line 1139, in test_large_content_length_truncated
    res = self.request('/cgi-bin/file1.py', 'POST', b'x', headers)
  File "/buildbot/buildarea/3.14.ware-freebsd.refleak/build/Lib/test/test_httpservers.py", line 131, in request
    self.connection.request(method, uri, body, headers)
    ~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/buildbot/buildarea/3.14.ware-freebsd.refleak/build/Lib/http/client.py", line 1358, in request
    self._send_request(method, url, body, headers, encode_chunked)
    ~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/buildbot/buildarea/3.14.ware-freebsd.refleak/build/Lib/http/client.py", line 1404, in _send_request
    self.endheaders(body, encode_chunked=encode_chunked)
    ~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/buildbot/buildarea/3.14.ware-freebsd.refleak/build/Lib/http/client.py", line 1353, in endheaders
    self._send_output(message_body, encode_chunked=encode_chunked)
    ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/buildbot/buildarea/3.14.ware-freebsd.refleak/build/Lib/http/client.py", line 1152, in _send_output
    self.send(chunk)
    ~~~~~~~~~^^^^^^^
  File "/buildbot/buildarea/3.14.ware-freebsd.refleak/build/Lib/http/client.py", line 1077, in send
    self.sock.sendall(data)
    ~~~~~~~~~~~~~~~~~^^^^^^
BrokenPipeError: [Errno 32] Broken pipe


Traceback (most recent call last):
  File "/buildbot/buildarea/3.14.ware-freebsd.refleak/build/Lib/test/libregrtest/single.py", line 236, in _runtest_env_changed_exc
    return
ResourceWarning: unclosed <socket.socket fd=5, family=2, type=1, proto=6, laddr=('127.0.0.1', 27602)>

reidenong pushed a commit to reidenong/cpython that referenced this pull request Jan 12, 2026
@skirpichev @reidenong
pythongh-143420: Clarify sequence behavior for slice indexes (python#…
7fcab74 
…143422)
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