Mercurial > hg
view tests/test-excessive-merge.t @ 30435:b86a448a2965
zstd: vendor python-zstandard 0.5.0
As the commit message for the previous changeset says, we wish
for zstd to be a 1st class citizen in Mercurial. To make that
happen, we need to enable Python to talk to the zstd C API. And
that requires bindings.
This commit vendors a copy of existing Python bindings. Why do we
need to vendor? As the commit message of the previous commit says,
relying on systems in the wild to have the bindings or zstd present
is a losing proposition. By distributing the zstd and bindings with
Mercurial, we significantly increase our chances that zstd will
work. Since zstd will deliver a better end-user experience by
achieving better performance, this benefits our users. Another
reason is that the Python bindings still aren't stable and the
API is somewhat fluid. While Mercurial could be coded to target
multiple versions of the Python bindings, it is safer to bundle
an explicit, known working version.
The added Python bindings are mostly a fully-featured interface
to the zstd C API. They allow one-shot operations, streaming,
reading and writing from objects implements the file object
protocol, dictionary compression, control over low-level compression
parameters, and more. The Python bindings work on Python 2.6,
2.7, and 3.3+ and have been tested on Linux and Windows. There are
CFFI bindings, but they are lacking compared to the C extension.
Upstream work will be needed before we can support zstd with PyPy.
But it will be possible.
The files added in this commit come from Git commit
e637c1b214d5f869cf8116c550dcae23ec13b677 from
https://github.com/indygreg/python-zstandard and are added without
modifications. Some files from the upstream repository have been
omitted, namely files related to continuous integration.
In the spirit of full disclosure, I'm the maintainer of the
"python-zstandard" project and have authored 100% of the code
added in this commit. Unfortunately, the Python bindings have
not been formally code reviewed by anyone. While I've tested
much of the code thoroughly (I even have tests that fuzz APIs),
there's a good chance there are bugs, memory leaks, not well
thought out APIs, etc. If someone wants to review the code and
send feedback to the GitHub project, it would be greatly
appreciated.
Despite my involvement with both projects, my opinions of code
style differ from Mercurial's. The code in this commit introduces
numerous code style violations in Mercurial's linters. So, the code
is excluded from most lints. However, some violations I agree with.
These have been added to the known violations ignore list for now.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Thu, 10 Nov 2016 22:15:58 -0800 |
parents | b7a966ce89ed |
children | 009d0283de5f |
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$ hg init $ echo foo > a $ echo foo > b $ hg add a b $ hg ci -m "test" $ echo blah > a $ hg ci -m "branch a" $ hg co 0 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo blah > b $ hg ci -m "branch b" created new head $ HGMERGE=true hg merge 1 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ hg ci -m "merge b/a -> blah" $ hg co 1 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ HGMERGE=true hg merge 2 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ hg ci -m "merge a/b -> blah" created new head $ hg log changeset: 4:2ee31f665a86 tag: tip parent: 1:96155394af80 parent: 2:92cc4c306b19 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: merge a/b -> blah changeset: 3:e16a66a37edd parent: 2:92cc4c306b19 parent: 1:96155394af80 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: merge b/a -> blah changeset: 2:92cc4c306b19 parent: 0:5e0375449e74 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: branch b changeset: 1:96155394af80 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: branch a changeset: 0:5e0375449e74 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: test $ hg debugindex --changelog rev offset length ..... linkrev nodeid p1 p2 (re) 0 0 60 ..... 0 5e0375449e74 000000000000 000000000000 (re) 1 60 62 ..... 1 96155394af80 5e0375449e74 000000000000 (re) 2 122 62 ..... 2 92cc4c306b19 5e0375449e74 000000000000 (re) 3 184 69 ..... 3 e16a66a37edd 92cc4c306b19 96155394af80 (re) 4 253 69 ..... 4 2ee31f665a86 96155394af80 92cc4c306b19 (re) revision 1 $ hg manifest --debug 1 79d7492df40aa0fa093ec4209be78043c181f094 644 a 2ed2a3912a0b24502043eae84ee4b279c18b90dd 644 b revision 2 $ hg manifest --debug 2 2ed2a3912a0b24502043eae84ee4b279c18b90dd 644 a 79d7492df40aa0fa093ec4209be78043c181f094 644 b revision 3 $ hg manifest --debug 3 79d7492df40aa0fa093ec4209be78043c181f094 644 a 79d7492df40aa0fa093ec4209be78043c181f094 644 b revision 4 $ hg manifest --debug 4 79d7492df40aa0fa093ec4209be78043c181f094 644 a 79d7492df40aa0fa093ec4209be78043c181f094 644 b $ hg debugindex a rev offset length ..... linkrev nodeid p1 p2 (re) 0 0 5 ..... 0 2ed2a3912a0b 000000000000 000000000000 (re) 1 5 6 ..... 1 79d7492df40a 2ed2a3912a0b 000000000000 (re) $ hg verify checking changesets checking manifests crosschecking files in changesets and manifests checking files 2 files, 5 changesets, 4 total revisions