view tests/test-debugbuilddag.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.

plain

  $ hg init
  $ hg debugbuilddag '+2:f +3:p2 @temp <f+4 @default /p2 +2' \
  > --config extensions.progress= --config progress.assume-tty=1 \
  > --config progress.delay=0 --config progress.refresh=0 \
  > --config progress.format=topic,bar,number \
  > --config progress.width=60
  \r (no-eol) (esc)
  building [                                          ]  0/12\r (no-eol) (esc)
  building [                                          ]  0/12\r (no-eol) (esc)
  building [==>                                       ]  1/12\r (no-eol) (esc)
  building [==>                                       ]  1/12\r (no-eol) (esc)
  building [======>                                   ]  2/12\r (no-eol) (esc)
  building [=========>                                ]  3/12\r (no-eol) (esc)
  building [=============>                            ]  4/12\r (no-eol) (esc)
  building [=============>                            ]  4/12\r (no-eol) (esc)
  building [=============>                            ]  4/12\r (no-eol) (esc)
  building [================>                         ]  5/12\r (no-eol) (esc)
  building [====================>                     ]  6/12\r (no-eol) (esc)
  building [=======================>                  ]  7/12\r (no-eol) (esc)
  building [===========================>              ]  8/12\r (no-eol) (esc)
  building [===========================>              ]  8/12\r (no-eol) (esc)
  building [==============================>           ]  9/12\r (no-eol) (esc)
  building [==================================>       ] 10/12\r (no-eol) (esc)
  building [=====================================>    ] 11/12\r (no-eol) (esc)
                                                              \r (no-eol) (esc)

tags
  $ cat .hg/localtags
  66f7d451a68b85ed82ff5fcc254daf50c74144bd f
  bebd167eb94d257ace0e814aeb98e6972ed2970d p2
dag
  $ hg debugdag -t -b
  +2:f
  +3:p2
  @temp*f+3
  @default*/p2+2:tip
tip
  $ hg id
  000000000000
glog
  $ hg log -G --template '{rev}: {desc} [{branches}] @ {date}\n'
  o  11: r11 [] @ 11.00
  |
  o  10: r10 [] @ 10.00
  |
  o    9: r9 [] @ 9.00
  |\
  | o  8: r8 [temp] @ 8.00
  | |
  | o  7: r7 [temp] @ 7.00
  | |
  | o  6: r6 [temp] @ 6.00
  | |
  | o  5: r5 [temp] @ 5.00
  | |
  o |  4: r4 [] @ 4.00
  | |
  o |  3: r3 [] @ 3.00
  | |
  o |  2: r2 [] @ 2.00
  |/
  o  1: r1 [] @ 1.00
  |
  o  0: r0 [] @ 0.00
  

overwritten files, starting on a non-default branch

  $ rm -r .hg
  $ hg init
  $ hg debugbuilddag '@start.@default.:f +3:p2 @temp <f+4 @default /p2 +2' -q -o
tags
  $ cat .hg/localtags
  f778700ebd50fcf282b23a4446bd155da6453eb6 f
  bbccf169769006e2490efd2a02f11c3d38d462bd p2
dag
  $ hg debugdag -t -b
  @start+1
  @default+1:f
  +3:p2
  @temp*f+3
  @default*/p2+2:tip
tip
  $ hg id
  000000000000
glog
  $ hg log -G --template '{rev}: {desc} [{branches}] @ {date}\n'
  o  11: r11 [] @ 11.00
  |
  o  10: r10 [] @ 10.00
  |
  o    9: r9 [] @ 9.00
  |\
  | o  8: r8 [temp] @ 8.00
  | |
  | o  7: r7 [temp] @ 7.00
  | |
  | o  6: r6 [temp] @ 6.00
  | |
  | o  5: r5 [temp] @ 5.00
  | |
  o |  4: r4 [] @ 4.00
  | |
  o |  3: r3 [] @ 3.00
  | |
  o |  2: r2 [] @ 2.00
  |/
  o  1: r1 [] @ 1.00
  |
  o  0: r0 [start] @ 0.00
  
glog of
  $ hg log -G --template '{rev}: {desc} [{branches}]\n' of
  o  11: r11 []
  |
  o  10: r10 []
  |
  o    9: r9 []
  |\
  | o  8: r8 [temp]
  | |
  | o  7: r7 [temp]
  | |
  | o  6: r6 [temp]
  | |
  | o  5: r5 [temp]
  | |
  o |  4: r4 []
  | |
  o |  3: r3 []
  | |
  o |  2: r2 []
  |/
  o  1: r1 []
  |
  o  0: r0 [start]
  
tags
  $ hg tags -v
  tip                               11:9ffe238a67a2
  p2                                 4:bbccf1697690 local
  f                                  1:f778700ebd50 local
cat of
  $ hg cat of --rev tip
  r11


new and mergeable files

  $ rm -r .hg
  $ hg init
  $ hg debugbuilddag '+2:f +3:p2 @temp <f+4 @default /p2 +2' -q -mn
dag
  $ hg debugdag -t -b
  +2:f
  +3:p2
  @temp*f+3
  @default*/p2+2:tip
tip
  $ hg id
  000000000000
glog
  $ hg log -G --template '{rev}: {desc} [{branches}] @ {date}\n'
  o  11: r11 [] @ 11.00
  |
  o  10: r10 [] @ 10.00
  |
  o    9: r9 [] @ 9.00
  |\
  | o  8: r8 [temp] @ 8.00
  | |
  | o  7: r7 [temp] @ 7.00
  | |
  | o  6: r6 [temp] @ 6.00
  | |
  | o  5: r5 [temp] @ 5.00
  | |
  o |  4: r4 [] @ 4.00
  | |
  o |  3: r3 [] @ 3.00
  | |
  o |  2: r2 [] @ 2.00
  |/
  o  1: r1 [] @ 1.00
  |
  o  0: r0 [] @ 0.00
  
glog mf
  $ hg log -G --template '{rev}: {desc} [{branches}]\n' mf
  o  11: r11 []
  |
  o  10: r10 []
  |
  o    9: r9 []
  |\
  | o  8: r8 [temp]
  | |
  | o  7: r7 [temp]
  | |
  | o  6: r6 [temp]
  | |
  | o  5: r5 [temp]
  | |
  o |  4: r4 []
  | |
  o |  3: r3 []
  | |
  o |  2: r2 []
  |/
  o  1: r1 []
  |
  o  0: r0 []
  

man r4
  $ hg manifest -r4
  mf
  nf0
  nf1
  nf2
  nf3
  nf4
cat r4 mf
  $ hg cat -r4 mf
  0 r0
  1
  2 r1
  3
  4 r2
  5
  6 r3
  7
  8 r4
  9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
man r8
  $ hg manifest -r8
  mf
  nf0
  nf1
  nf5
  nf6
  nf7
  nf8
cat r8 mf
  $ hg cat -r8 mf
  0 r0
  1
  2 r1
  3
  4
  5
  6
  7
  8
  9
  10 r5
  11
  12 r6
  13
  14 r7
  15
  16 r8
  17
  18
  19
  20
  21
  22
  23
man
  $ hg manifest --rev tip
  mf
  nf0
  nf1
  nf10
  nf11
  nf2
  nf3
  nf4
  nf5
  nf6
  nf7
  nf8
  nf9
cat mf
  $ hg cat mf --rev tip
  0 r0
  1
  2 r1
  3
  4 r2
  5
  6 r3
  7
  8 r4
  9
  10 r5
  11
  12 r6
  13
  14 r7
  15
  16 r8
  17
  18 r9
  19
  20 r10
  21
  22 r11
  23