view tests/test-convert-svn-sink.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 svn13

  $ svnupanddisplay()
  > {
  >     (
  >        cd $1;
  >        svn up -q;
  >        svn st -v | sed 's/  */ /g' | sort
  >        limit=''
  >        if [ $2 -gt 0 ]; then
  >            limit="--limit=$2"
  >        fi
  >        svn log --xml -v $limit | $PYTHON "$TESTDIR/svnxml.py"
  >     )
  > }

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > convert =
  > EOF

  $ hg init a

Add

  $ echo a > a/a
  $ mkdir -p a/d1/d2
  $ echo b > a/d1/d2/b
  $ hg --cwd a ci -d '0 0' -A -m 'add a file'
  adding a
  adding d1/d2/b

Modify

  $ svn-safe-append.py a a/a
  $ hg --cwd a ci -d '1 0' -m 'modify a file'
  $ hg --cwd a tip -q
  1:e0e2b8a9156b

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn repository 'a-hg'
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  1 add a file
  0 modify a file
  $ svnupanddisplay a-hg-wc 2
   2 1 test d1
   2 1 test d1/d2 (glob)
   2 1 test d1/d2/b (glob)
   2 2 test .
   2 2 test a
  revision: 2
  author: test
  msg: modify a file
   M /a
  revision: 1
  author: test
  msg: add a file
   A /a
   A /d1
   A /d1/d2
   A /d1/d2/b
  $ ls a a-hg-wc
  a:
  a
  d1
  
  a-hg-wc:
  a
  d1
  $ cmp a/a a-hg-wc/a

Rename

  $ hg --cwd a mv a b
  $ hg --cwd a ci -d '2 0' -m 'rename a file'
  $ hg --cwd a tip -q
  2:eb5169441d43

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 rename a file
  $ svnupanddisplay a-hg-wc 1
   3 1 test d1
   3 1 test d1/d2 (glob)
   3 1 test d1/d2/b (glob)
   3 3 test .
   3 3 test b
  revision: 3
  author: test
  msg: rename a file
   D /a
   A /b (from /a@2)
  $ ls a a-hg-wc
  a:
  b
  d1
  
  a-hg-wc:
  b
  d1

Copy

  $ hg --cwd a cp b c

  $ hg --cwd a ci -d '3 0' -m 'copy a file'
  $ hg --cwd a tip -q
  3:60effef6ab48

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 copy a file
  $ svnupanddisplay a-hg-wc 1
   4 1 test d1
   4 1 test d1/d2 (glob)
   4 1 test d1/d2/b (glob)
   4 3 test b
   4 4 test .
   4 4 test c
  revision: 4
  author: test
  msg: copy a file
   A /c (from /b@3)
  $ ls a a-hg-wc
  a:
  b
  c
  d1
  
  a-hg-wc:
  b
  c
  d1

  $ hg --cwd a rm b

Remove

  $ hg --cwd a ci -d '4 0' -m 'remove a file'
  $ hg --cwd a tip -q
  4:87bbe3013fb6

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 remove a file
  $ svnupanddisplay a-hg-wc 1
   5 1 test d1
   5 1 test d1/d2 (glob)
   5 1 test d1/d2/b (glob)
   5 4 test c
   5 5 test .
  revision: 5
  author: test
  msg: remove a file
   D /b
  $ ls a a-hg-wc
  a:
  c
  d1
  
  a-hg-wc:
  c
  d1

Executable

#if execbit
  $ chmod +x a/c
#else
  $ echo fake >> a/c
#endif
  $ hg --cwd a ci -d '5 0' -m 'make a file executable'
#if execbit
  $ hg --cwd a tip -q
  5:ff42e473c340
#else
  $ hg --cwd a tip -q
  5:817a700c8cf1
#endif

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 make a file executable
  $ svnupanddisplay a-hg-wc 1
   6 1 test d1
   6 1 test d1/d2 (glob)
   6 1 test d1/d2/b (glob)
   6 6 test .
   6 6 test c
  revision: 6
  author: test
  msg: make a file executable
   M /c
#if execbit
  $ test -x a-hg-wc/c
#endif

#if symlink

Symlinks

  $ ln -s a/missing a/link
  $ hg --cwd a commit -Am 'add symlink'
  adding link
  $ hg --cwd a mv link newlink
  $ hg --cwd a commit -m 'move symlink'
  $ hg convert -d svn a a-svnlink
  initializing svn repository 'a-svnlink'
  initializing svn working copy 'a-svnlink-wc'
  scanning source...
  sorting...
  converting...
  7 add a file
  6 modify a file
  5 rename a file
  4 copy a file
  3 remove a file
  2 make a file executable
  1 add symlink
  0 move symlink
  $ svnupanddisplay a-svnlink-wc 1
   8 1 test d1
   8 1 test d1/d2
   8 1 test d1/d2/b
   8 6 test c
   8 8 test .
   8 8 test newlink
  revision: 8
  author: test
  msg: move symlink
   D /link
   A /newlink (from /link@7)

Make sure our changes don't affect the rest of the test cases

  $ hg --cwd a up 5
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg --cwd a --config extensions.strip= strip -r 6
  saved backup bundle to $TESTTMP/a/.hg/strip-backup/bd4f7b7a7067-ed505e42-backup.hg (glob)

#endif

Convert with --full adds and removes files that didn't change

  $ touch a/f
  $ hg -R a ci -Aqmf
  $ echo "rename c d" > filemap
  $ hg convert -d svn a --filemap filemap --full
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 f
  $ svnupanddisplay a-hg-wc 1
   7 7 test .
   7 7 test d
   7 7 test f
  revision: 7
  author: test
  msg: f
   D /c
   A /d
   D /d1
   A /f

  $ rm -rf a a-hg a-hg-wc


Executable in new directory

  $ hg init a

  $ mkdir a/d1
  $ echo a > a/d1/a
#if execbit
  $ chmod +x a/d1/a
#else
  $ echo fake >> a/d1/a
#endif
  $ hg --cwd a ci -d '0 0' -A -m 'add executable file in new directory'
  adding d1/a

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn repository 'a-hg'
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 add executable file in new directory
  $ svnupanddisplay a-hg-wc 1
   1 1 test .
   1 1 test d1
   1 1 test d1/a (glob)
  revision: 1
  author: test
  msg: add executable file in new directory
   A /d1
   A /d1/a
#if execbit
  $ test -x a-hg-wc/d1/a
#endif

Copy to new directory

  $ mkdir a/d2
  $ hg --cwd a cp d1/a d2/a
  $ hg --cwd a ci -d '1 0' -A -m 'copy file to new directory'

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 copy file to new directory
  $ svnupanddisplay a-hg-wc 1
   2 1 test d1
   2 1 test d1/a (glob)
   2 2 test .
   2 2 test d2
   2 2 test d2/a (glob)
  revision: 2
  author: test
  msg: copy file to new directory
   A /d2
   A /d2/a (from /d1/a@1)

Branchy history

  $ hg init b
  $ echo base > b/b
  $ hg --cwd b ci -d '0 0' -Ambase
  adding b

  $ svn-safe-append.py left-1 b/b
  $ echo left-1 > b/left-1
  $ hg --cwd b ci -d '1 0' -Amleft-1
  adding left-1

  $ svn-safe-append.py left-2 b/b
  $ echo left-2 > b/left-2
  $ hg --cwd b ci -d '2 0' -Amleft-2
  adding left-2

  $ hg --cwd b up 0
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

  $ svn-safe-append.py right-1 b/b
  $ echo right-1 > b/right-1
  $ hg --cwd b ci -d '3 0' -Amright-1
  adding right-1
  created new head

  $ svn-safe-append.py right-2 b/b
  $ echo right-2 > b/right-2
  $ hg --cwd b ci -d '4 0' -Amright-2
  adding right-2

  $ hg --cwd b up -C 2
  3 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ hg --cwd b merge
  merging b
  warning: conflicts while merging b! (edit, then use 'hg resolve --mark')
  2 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]
  $ hg --cwd b revert -r 2 b
  $ hg --cwd b resolve -m b
  (no more unresolved files)
  $ hg --cwd b ci -d '5 0' -m 'merge'

Expect 4 changes

  $ hg convert -d svn b
  assuming destination b-hg
  initializing svn repository 'b-hg'
  initializing svn working copy 'b-hg-wc'
  scanning source...
  sorting...
  converting...
  5 base
  4 left-1
  3 left-2
  2 right-1
  1 right-2
  0 merge

  $ svnupanddisplay b-hg-wc 0
   4 2 test left-1
   4 3 test b
   4 3 test left-2
   4 4 test .
   4 4 test right-1
   4 4 test right-2
  revision: 4
  author: test
  msg: merge
   A /right-1
   A /right-2
  revision: 3
  author: test
  msg: left-2
   M /b
   A /left-2
  revision: 2
  author: test
  msg: left-1
   M /b
   A /left-1
  revision: 1
  author: test
  msg: base
   A /b

Tags are not supported, but must not break conversion

  $ rm -rf a a-hg a-hg-wc
  $ hg init a
  $ echo a > a/a
  $ hg --cwd a ci -d '0 0' -A -m 'Add file a'
  adding a
  $ hg --cwd a tag -d '1 0' -m 'Tagged as v1.0' v1.0

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn repository 'a-hg'
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  1 Add file a
  0 Tagged as v1.0
  writing Subversion tags is not yet implemented
  $ svnupanddisplay a-hg-wc 2
   2 1 test a
   2 2 test .
   2 2 test .hgtags
  revision: 2
  author: test
  msg: Tagged as v1.0
   A /.hgtags
  revision: 1
  author: test
  msg: Add file a
   A /a
  $ rm -rf a a-hg a-hg-wc