view tests/test-inherit-mode.t @ 33289:abd7dedbaa36

sparse: vendor Facebook-developed extension

Facebook has developed an extension to enable "sparse" checkouts -
a working directory with a subset of files. This feature is a critical
component in enabling repositories to scale to infinite number of
files while retaining reasonable performance. It's worth noting
that sparse checkout is only one possible solution to this problem:
another is virtual filesystems that realize files on first access.
But given that virtual filesystems may not be accessible to all
users, sparse checkout is necessary as a fallback.

Per mailing list discussion at
https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-March/095868.html
we want to add sparse checkout to the Mercurial distribution via
roughly the following mechanism:

1. Vendor extension as-is with minimal modifications (this patch)
2. Refactor extension so it is more clearly experimental and inline
   with Mercurial practices
3. Move code from extension into core where possible
4. Drop experimental labeling and/or move feature into core
   after sign-off from narrow clone feature owners

This commit essentially copies the sparse extension and tests
from revision 71e0a2aeca92a4078fe1b8c76e32c88ff1929737 of the
https://bitbucket.org/facebook/hg-experimental repository.

A list of modifications made as part of vendoring is as follows:

* "EXPERIMENTAL" added to module docstring
* Imports were changed to match Mercurial style conventions
* "testedwith" value was updated to core Mercurial special value and
  comment boilerplate was inserted
* A "clone_sparse" function was renamed to "clonesparse" to appease
  the style checker
* Paths to the sparse extension in tests reflect built-in location
* test-sparse-extensions.t was renamed to test-sparse-fsmonitor.t
  and references to "simplecache" were removed. The test always skips
  because it isn't trivial to run it given the way we currently run
  fsmonitor tests
* A double empty line was removed from test-sparse-profiles.t

There are aspects of the added code that are obviously not ideal.
The goal is to make a minimal number of modifications as part of
the vendoring to make it easier to track changes from the original
implementation. Refactoring will occur in subsequent patches.

#require unix-permissions

test that new files created in .hg inherit the permissions from .hg/store

  $ mkdir dir

just in case somebody has a strange $TMPDIR

  $ chmod g-s dir
  $ cd dir

  $ cat >printmodes.py <<EOF
  > import os, sys
  > 
  > allnames = []
  > isdir = {}
  > for root, dirs, files in os.walk(sys.argv[1]):
  >     for d in dirs:
  >         name = os.path.join(root, d)
  >         isdir[name] = 1
  >         allnames.append(name)
  >     for f in files:
  >         name = os.path.join(root, f)
  >         allnames.append(name)
  > allnames.sort()
  > for name in allnames:
  >     suffix = name in isdir and '/' or ''
  >     print '%05o %s%s' % (os.lstat(name).st_mode & 07777, name, suffix)
  > EOF

  $ cat >mode.py <<EOF
  > import sys
  > import os
  > print '%05o' % os.lstat(sys.argv[1]).st_mode
  > EOF

  $ umask 077

  $ hg init repo
  $ cd repo

  $ chmod 0770 .hg/store

before commit
store can be written by the group, other files cannot
store is setgid

  $ $PYTHON ../printmodes.py .
  00700 ./.hg/
  00600 ./.hg/00changelog.i
  00600 ./.hg/requires
  00770 ./.hg/store/

  $ mkdir dir
  $ touch foo dir/bar
  $ hg ci -qAm 'add files'

after commit
working dir files can only be written by the owner
files created in .hg can be written by the group
(in particular, store/**, dirstate, branch cache file, undo files)
new directories are setgid

  $ $PYTHON ../printmodes.py .
  00700 ./.hg/
  00600 ./.hg/00changelog.i
  00770 ./.hg/cache/
  00660 ./.hg/cache/branch2-served
  00660 ./.hg/cache/rbc-names-v1
  00660 ./.hg/cache/rbc-revs-v1
  00660 ./.hg/dirstate
  00660 ./.hg/last-message.txt
  00600 ./.hg/requires
  00770 ./.hg/store/
  00660 ./.hg/store/00changelog.i
  00660 ./.hg/store/00manifest.i
  00770 ./.hg/store/data/
  00770 ./.hg/store/data/dir/
  00660 ./.hg/store/data/dir/bar.i
  00660 ./.hg/store/data/foo.i
  00660 ./.hg/store/fncache
  00660 ./.hg/store/phaseroots
  00660 ./.hg/store/undo
  00660 ./.hg/store/undo.backupfiles
  00660 ./.hg/store/undo.phaseroots
  00660 ./.hg/undo.backup.dirstate
  00660 ./.hg/undo.bookmarks
  00660 ./.hg/undo.branch
  00660 ./.hg/undo.desc
  00660 ./.hg/undo.dirstate
  00700 ./dir/
  00600 ./dir/bar
  00600 ./foo

  $ umask 007
  $ hg init ../push

before push
group can write everything

  $ $PYTHON ../printmodes.py ../push
  00770 ../push/.hg/
  00660 ../push/.hg/00changelog.i
  00660 ../push/.hg/requires
  00770 ../push/.hg/store/

  $ umask 077
  $ hg -q push ../push

after push
group can still write everything

  $ $PYTHON ../printmodes.py ../push
  00770 ../push/.hg/
  00660 ../push/.hg/00changelog.i
  00770 ../push/.hg/cache/
  00660 ../push/.hg/cache/branch2-base
  00660 ../push/.hg/dirstate
  00660 ../push/.hg/requires
  00770 ../push/.hg/store/
  00660 ../push/.hg/store/00changelog.i
  00660 ../push/.hg/store/00manifest.i
  00770 ../push/.hg/store/data/
  00770 ../push/.hg/store/data/dir/
  00660 ../push/.hg/store/data/dir/bar.i
  00660 ../push/.hg/store/data/foo.i
  00660 ../push/.hg/store/fncache
  00660 ../push/.hg/store/undo
  00660 ../push/.hg/store/undo.backupfiles
  00660 ../push/.hg/store/undo.phaseroots
  00660 ../push/.hg/undo.bookmarks
  00660 ../push/.hg/undo.branch
  00660 ../push/.hg/undo.desc
  00660 ../push/.hg/undo.dirstate


Test that we don't lose the setgid bit when we call chmod.
Not all systems support setgid directories (e.g. HFS+), so
just check that directories have the same mode.

  $ cd ..
  $ hg init setgid
  $ cd setgid
  $ chmod g+rwx .hg/store
  $ chmod g+s .hg/store 2> /dev/null || true
  $ mkdir dir
  $ touch dir/file
  $ hg ci -qAm 'add dir/file'
  $ storemode=`$PYTHON ../mode.py .hg/store`
  $ dirmode=`$PYTHON ../mode.py .hg/store/data/dir`
  $ if [ "$storemode" != "$dirmode" ]; then
  >  echo "$storemode != $dirmode"
  > fi
  $ cd ..

  $ cd .. # g-s dir