annotate tests/test-sparse.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.

test sparse

  $ hg init myrepo
  $ cd myrepo
  $ cat > .hg/hgrc <<EOF
  > [extensions]
  > sparse=
  > strip=
  > EOF

  $ echo a > show
  $ echo x > hide
  $ hg ci -Aqm 'initial'

  $ echo b > show
  $ echo y > hide
  $ echo aa > show2
  $ echo xx > hide2
  $ hg ci -Aqm 'two'

Verify basic --include

  $ hg up -q 0
  $ hg sparse --include 'hide'
  $ ls
  hide

Absolute paths outside the repo should just be rejected

  $ hg sparse --include /foo/bar
  warning: paths cannot start with /, ignoring: ['/foo/bar']
  $ hg sparse --include '$TESTTMP/myrepo/hide'

  $ hg sparse --include '/root'
  warning: paths cannot start with /, ignoring: ['/root']

Verify commiting while sparse includes other files

  $ echo z > hide
  $ hg ci -Aqm 'edit hide'
  $ ls
  hide
  $ hg manifest
  hide
  show

Verify --reset brings files back

  $ hg sparse --reset
  $ ls
  hide
  show
  $ cat hide
  z
  $ cat show
  a

Verify 'hg sparse' default output

  $ hg up -q null
  $ hg sparse --include 'show*'

  $ hg sparse
  [include]
  show*
  [exclude]
  
  
Verify update only writes included files

  $ hg up -q 0
  $ ls
  show

  $ hg up -q 1
  $ ls
  show
  show2

Verify status only shows included files

  $ touch hide
  $ touch hide3
  $ echo c > show
  $ hg status
  M show

Adding an excluded file should fail

  $ hg add hide3
  abort: cannot add 'hide3' - it is outside the sparse checkout
  (include file with `hg sparse --include <pattern>` or use `hg add -s <file>` to include file directory while adding)
  [255]

Verify deleting sparseness while a file has changes fails

  $ hg sparse --delete 'show*'
  pending changes to 'hide'
  abort: cannot change sparseness due to pending changes (delete the files or use --force to bring them back dirty)
  [255]

Verify deleting sparseness with --force brings back files

  $ hg sparse --delete -f 'show*'
  pending changes to 'hide'
  $ ls
  hide
  hide2
  hide3
  show
  show2
  $ hg st
  M hide
  M show
  ? hide3

Verify editing sparseness fails if pending changes

  $ hg sparse --include 'show*'
  pending changes to 'hide'
  abort: could not update sparseness due to pending changes
  [255]

Verify adding sparseness hides files

  $ hg sparse --exclude -f 'hide*'
  pending changes to 'hide'
  $ ls
  hide
  hide3
  show
  show2
  $ hg st
  M show

  $ hg up -qC .
  $ hg purge --all --config extensions.purge=
  $ ls
  show
  show2

Verify rebase temporarily includes excluded files

  $ hg rebase -d 1 -r 2 --config extensions.rebase=
  rebasing 2:b91df4f39e75 "edit hide" (tip)
  temporarily included 1 file(s) in the sparse checkout for merging
  merging hide
  warning: conflicts while merging hide! (edit, then use 'hg resolve --mark')
  unresolved conflicts (see hg resolve, then hg rebase --continue)
  [1]

  $ hg sparse
  [include]
  
  [exclude]
  hide*
  
  Temporarily Included Files (for merge/rebase):
  hide

  $ cat hide
  <<<<<<< dest:   39278f7c08a9 - test: two
  y
  =======
  z
  >>>>>>> source: b91df4f39e75 - test: edit hide

Verify aborting a rebase cleans up temporary files

  $ hg rebase --abort --config extensions.rebase=
  cleaned up 1 temporarily added file(s) from the sparse checkout
  rebase aborted
  $ rm hide.orig

  $ ls
  show
  show2

Verify merge fails if merging excluded files

  $ hg up -q 1
  $ hg merge -r 2
  temporarily included 1 file(s) in the sparse checkout for merging
  merging hide
  warning: conflicts while merging hide! (edit, then use 'hg resolve --mark')
  0 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 sparse
  [include]
  
  [exclude]
  hide*
  
  Temporarily Included Files (for merge/rebase):
  hide

  $ hg up -C .
  cleaned up 1 temporarily added file(s) from the sparse checkout
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg sparse
  [include]
  
  [exclude]
  hide*
  

Verify strip -k resets dirstate correctly

  $ hg status
  $ hg sparse
  [include]
  
  [exclude]
  hide*
  
  $ hg log -r . -T '{rev}\n' --stat
  1
   hide  |  2 +-
   hide2 |  1 +
   show  |  2 +-
   show2 |  1 +
   4 files changed, 4 insertions(+), 2 deletions(-)
  
  $ hg strip -r . -k
  saved backup bundle to $TESTTMP/myrepo/.hg/strip-backup/39278f7c08a9-ce59e002-backup.hg (glob)
  $ hg status
  M show
  ? show2

Verify rebase succeeds if all changed files are in sparse checkout

  $ hg commit -Aqm "add show2"
  $ hg rebase -d 1 --config extensions.rebase=
  rebasing 2:bdde55290160 "add show2" (tip)
  saved backup bundle to $TESTTMP/myrepo/.hg/strip-backup/bdde55290160-216ed9c6-backup.hg (glob)

Verify log --sparse only shows commits that affect the sparse checkout

  $ hg log -T '{rev} '
  2 1 0  (no-eol)
  $ hg log --sparse -T '{rev} '
  2 0  (no-eol)

Test status on a file in a subdir

  $ mkdir -p dir1/dir2
  $ touch dir1/dir2/file
  $ hg sparse -I dir1/dir2
  $ hg status
  ? dir1/dir2/file

Test that add -s adds dirs to sparse profile

  $ hg sparse --reset
  $ hg sparse --include empty
  $ hg sparse
  [include]
  empty
  [exclude]
  
  

  $ mkdir add
  $ touch add/foo
  $ touch add/bar
  $ hg add add/foo
  abort: cannot add 'add/foo' - it is outside the sparse checkout
  (include file with `hg sparse --include <pattern>` or use `hg add -s <file>` to include file directory while adding)
  [255]
  $ hg add -s add/foo
  $ hg st
  A add/foo
  ? add/bar
  $ hg sparse
  [include]
  add
  empty
  [exclude]
  
  
  $ hg add -s add/*
  add/foo already tracked!
  $ hg st
  A add/bar
  A add/foo
  $ hg sparse
  [include]
  add
  empty
  [exclude]
  
  

  $ cd ..

Test non-sparse repos work while sparse is loaded
  $ hg init sparserepo
  $ hg init nonsparserepo
  $ cd sparserepo
  $ cat > .hg/hgrc <<EOF
  > [extensions]
  > sparse=
  > EOF
  $ cd ../nonsparserepo
  $ echo x > x && hg add x && hg commit -qAm x
  $ cd ../sparserepo
  $ hg clone ../nonsparserepo ../nonsparserepo2
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

Test debugrebuilddirstate
  $ cd ../sparserepo
  $ touch included
  $ touch excluded
  $ hg add included excluded
  $ hg commit -m 'a commit' -q
  $ cp .hg/dirstate ../dirstateboth
  $ hg sparse -X excluded
  $ cp ../dirstateboth .hg/dirstate
  $ hg debugrebuilddirstate
  $ hg debugdirstate
  n   0         -1 unset               included

Test debugdirstate --minimal where file is in the parent manifest but not the
dirstate
  $ hg sparse -X included
  $ hg debugdirstate
  $ cp .hg/dirstate ../dirstateallexcluded
  $ hg sparse --reset
  $ hg sparse -X excluded
  $ cp ../dirstateallexcluded .hg/dirstate
  $ touch includedadded
  $ hg add includedadded
  $ hg debugdirstate --nodates
  a   0         -1 unset               includedadded
  $ hg debugrebuilddirstate --minimal
  $ hg debugdirstate --nodates
  n   0         -1 unset               included
  a   0         -1 * includedadded (glob)

Test debugdirstate --minimal where a file is not in parent manifest
but in the dirstate. This should take into account excluded files in the
manifest
  $ cp ../dirstateboth .hg/dirstate
  $ touch includedadded
  $ hg add includedadded
  $ touch excludednomanifest
  $ hg add excludednomanifest
  $ cp .hg/dirstate ../moreexcluded
  $ hg forget excludednomanifest
  $ rm excludednomanifest
  $ hg sparse -X excludednomanifest
  $ cp ../moreexcluded .hg/dirstate
  $ hg manifest
  excluded
  included
We have files in the dirstate that are included and excluded. Some are in the
manifest and some are not.
  $ hg debugdirstate --nodates
  n 644          0 * excluded (glob)
  a   0         -1 * excludednomanifest (glob)
  n 644          0 * included (glob)
  a   0         -1 * includedadded (glob)
  $ hg debugrebuilddirstate --minimal
  $ hg debugdirstate --nodates
  n 644          0 * included (glob)
  a   0         -1 * includedadded (glob)