view tests/test-py3-commands.t @ 35121:66c5a8cf2868

lfs: import the Facebook git-lfs client extension

The purpose of this is the same as the built-in largefiles extension- to handle
huge files outside of the normal storage system, generally to keep the amount of
data cloned to a lower amount.  There are several benefits of implementing the
git-lfs protocol, instead of using the largefiles extension:

  - Bitbucket and Github support (and probably wider support in 3rd party
    hosting sites in general). [1][2]

  - The number of hg internals monkey patched are several orders of magnitude
    lower, so it will be easier to reason about and maintain.  Future commands
    will likely just work, without requiring various wrappers.

  - The "standin" files are only written to the filelog, not the disk.  That
    should avoid weird edge cases where the largefile and standin files get out
    of sync. [3]  It also avoids the occasional printing of the "hidden" standin
    file in various messages.

  - Filesets like size() will work, even if the file isn't present.  (It always
    says 41 bytes for largefiles, whether present or not.)

The only place that I see where largefiles comes out on top is that it works
with `hg serve` for simple sharing, without external infrastructure.  Getting
lfs-test-server working was a hassle, and took awhile to figure out.  Maybe we
can do something to make it work in the future.

Long term, I expect that this will be highly preferred over largefiles.  But if
we are to recommend this to largefile users, there are some UI issues to
bikeshed.  Until they are resolved, I've marked this experimental, and am not
putting a pointer to this in the largefiles help.  The (non exhaustive) list of
issues I've seen so far are:

  - It isn't sufficient to just enable the largefiles extension- you have to
    explicitly add a file with --large before it will pay attention to the
    configured sizes and patterns on future adds.  The justification being that
    once you use it, you're stuck with it.  I've seen people confused by this,
    and haven't liked it myself.  But it's also saved me a few times.  Should we
    do something like have a specific enabling config setting that must be set
    in the local repo config, so that enabling this extension in the user or
    system hgrc doesn't silently start storing lfs files?

  - The largefiles extension adds a repo requirement when the first largefile is
    committed, so that the extension must always be enabled in the future.  This
    extension is not doing that, and since I only enabled it locally to avoid
    infecting other repos, I got a cryptic error about missing flag processors
    when I cloned.  Is there no repo requirement due to shallow/narrow clone
    considerations (or other future advanced things)?

  - In the (small amount of) reading I've done about the git implementation, it
    seems that the files and sizes are stored in a tracked .gitattributes file.
    I think a tracked file for this would be extremely useful for consistency
    across developers, but this kind of touches on the tracked hgrc file
    proposal a few months back.

  - The git client can specify file patterns, not just sizes.

  - The largefiles extension has a cache directory in the local repo, but also a
    system wide one.  We should probably implement a system wide cache too, so
    that multiple clones don't have to refetch the files from the server.

  - Jun mentioned other missing features, like SSH authentication, gc, etc.

The code corresponds to c0492b73c7ef in hg-experimental. [4]  The only tweaks
are to load the extension in the tests with 'lfs=' instead of
'lfs=$TESTDIR/../hgext3rd/lfs', change the import in the *.py test to hgext
(from hgext3rd), add the 'testedwith' declaration, and mark it experimental for
now.  The infinite-push, p4fastimport, and remotefilelog tests were left behind.

The devel-warnings for unregistered config options are not corrected yet, nor
are the import check warnings.

[1] https://www.mercurial-scm.org/pipermail/mercurial/2017-November/050699.html
[2] https://bitbucket.org/site/master/issues/3843/largefiles-support-bb-3903
[3] https://bz.mercurial-scm.org/show_bug.cgi?id=5738
[4] https://bitbucket.org/facebook/hg-experimental

#require py3exe

This test helps in keeping a track on which commands we can run on
Python 3 and see what kind of errors are coming up.
The full traceback is hidden to have a stable output.
  $ HGBIN=`which hg`

  $ for cmd in version debuginstall ; do
  >   echo $cmd
  >   $PYTHON3 $HGBIN $cmd 2>&1 2>&1 | tail -1
  > done
  version
  warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  debuginstall
  no problems detected

#if test-repo
Make a clone so that any features in the developer's .hg/hgrc that
might confuse Python 3 don't break this test. When we can do commit in
Python 3, we'll stop doing this. We use e76ed1e480ef for the clone
because it has different files than 273ce12ad8f1, so we can test both
`files` from dirstate and `files` loaded from a specific revision.

  $ hg clone -r e76ed1e480ef "`dirname "$TESTDIR"`" testrepo 2>&1 | tail -1
  15 files updated, 0 files merged, 0 files removed, 0 files unresolved

Test using -R, which exercises some URL code:
  $ $PYTHON3 $HGBIN -R testrepo files -r 273ce12ad8f1 | tail -1
  testrepo/tkmerge

Now prove `hg files` is reading the whole manifest. We have to grep
out some potential warnings that come from hgrc as yet.
  $ cd testrepo
  $ $PYTHON3 $HGBIN files -r 273ce12ad8f1
  .hgignore
  PKG-INFO
  README
  hg
  mercurial/__init__.py
  mercurial/byterange.py
  mercurial/fancyopts.py
  mercurial/hg.py
  mercurial/mdiff.py
  mercurial/revlog.py
  mercurial/transaction.py
  notes.txt
  setup.py
  tkmerge

  $ $PYTHON3 $HGBIN files -r 273ce12ad8f1 | wc -l
  \s*14 (re)
  $ $PYTHON3 $HGBIN files | wc -l
  \s*15 (re)

Test if log-like commands work:

  $ $PYTHON3 $HGBIN tip
  changeset:   10:e76ed1e480ef
  tag:         tip
  user:        [e-mail]
  date:        Tue May 03 23:37:43 2005 -0800
  summary:     Fix linking of changeset revs when merging
  

  $ $PYTHON3 $HGBIN log -r0
  changeset:   0:9117c6561b0b
  user:        [e-mail]
  date:        Tue May 03 13:16:10 2005 -0800
  summary:     Add back links from file revisions to changeset revisions
  

  $ cd ..
#endif

Test if `hg config` works:

  $ $PYTHON3 $HGBIN config
  devel.all-warnings=true
  devel.default-date=0 0
  largefiles.usercache=$TESTTMP/.cache/largefiles
  ui.slash=True
  ui.interactive=False
  ui.mergemarkers=detailed
  ui.promptecho=True
  web.address=localhost
  web.ipv6=False

  $ cat > included-hgrc <<EOF
  > [extensions]
  > babar = imaginary_elephant
  > EOF
  $ cat >> $HGRCPATH <<EOF
  > %include $TESTTMP/included-hgrc
  > EOF
  $ $PYTHON3 $HGBIN version | tail -1
  *** failed to import extension babar from imaginary_elephant: *: 'imaginary_elephant' (glob)
  warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

  $ rm included-hgrc
  $ touch included-hgrc

Test bytes-ness of policy.policy with HGMODULEPOLICY

  $ HGMODULEPOLICY=py
  $ export HGMODULEPOLICY
  $ $PYTHON3 `which hg` debuginstall 2>&1 2>&1 | tail -1
  no problems detected

`hg init` can create empty repos
`hg status works fine`
`hg summary` also works!

  $ $PYTHON3 `which hg` init py3repo
  $ cd py3repo
  $ echo "This is the file 'iota'." > iota
  $ $PYTHON3 $HGBIN status
  ? iota
  $ $PYTHON3 $HGBIN add iota
  $ $PYTHON3 $HGBIN status
  A iota
  $ hg diff --nodates --git
  diff --git a/iota b/iota
  new file mode 100644
  --- /dev/null
  +++ b/iota
  @@ -0,0 +1,1 @@
  +This is the file 'iota'.
  $ $PYTHON3 $HGBIN commit --message 'commit performed in Python 3'
  $ $PYTHON3 $HGBIN status

  $ mkdir A
  $ echo "This is the file 'mu'." > A/mu
  $ $PYTHON3 $HGBIN addremove
  adding A/mu
  $ $PYTHON3 $HGBIN status
  A A/mu
  $ HGEDITOR='echo message > ' $PYTHON3 $HGBIN commit
  $ $PYTHON3 $HGBIN status
  $ $PYHON3 $HGBIN summary
  parent: 1:e1e9167203d4 tip
   message
  branch: default
  commit: (clean)
  update: (current)
  phases: 2 draft

Test weird unicode-vs-bytes stuff

  $ $PYTHON3 $HGBIN help | egrep -v '^ |^$'
  Mercurial Distributed SCM
  list of commands:
  additional help topics:
  (use 'hg help -v' to show built-in aliases and global options)

  $ $PYTHON3 $HGBIN help help | egrep -v '^ |^$'
  hg help [-ecks] [TOPIC]
  show help for a given topic or a help overview
  options ([+] can be repeated):
  (some details hidden, use --verbose to show complete help)

  $ $PYTHON3 $HGBIN help -k notopic
  abort: no matches
  (try 'hg help' for a list of topics)
  [255]

Prove the repo is valid using the Python 2 `hg`:
  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  2 files, 2 changesets, 2 total revisions
  $ hg log
  changeset:   1:e1e9167203d4
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     message
  
  changeset:   0:71c96e924262
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     commit performed in Python 3
  

  $ $PYTHON3 $HGBIN log -G
  @  changeset:   1:e1e9167203d4
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     message
  |
  o  changeset:   0:71c96e924262
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     commit performed in Python 3
  
  $ $PYTHON3 $HGBIN log -Tjson
  [
   {
    "rev": 1,
    "node": "e1e9167203d450ca2f558af628955b5f5afd4489",
    "branch": "default",
    "phase": "draft",
    "user": "test",
    "date": [0, 0],
    "desc": "message",
    "bookmarks": [],
    "tags": ["tip"],
    "parents": ["71c96e924262969ff0d8d3d695b0f75412ccc3d8"]
   },
   {
    "rev": 0,
    "node": "71c96e924262969ff0d8d3d695b0f75412ccc3d8",
    "branch": "default",
    "phase": "draft",
    "user": "test",
    "date": [0, 0],
    "desc": "commit performed in Python 3",
    "bookmarks": [],
    "tags": [],
    "parents": ["0000000000000000000000000000000000000000"]
   }
  ]

Show that update works now!

  $ $PYTHON3 $HGBIN up 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ $PYTHON3 $HGBIN identify
  71c96e924262

branches and bookmarks also works!

  $ $PYTHON3 $HGBIN branches
  default                        1:e1e9167203d4
  $ $PYTHON3 $HGBIN bookmark book
  $ $PYTHON3 $HGBIN bookmarks
   * book                      0:71c96e924262