view tests/test-show-work.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.

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

  $ hg init repo0
  $ cd repo0

Command works on an empty repo

  $ hg show work

Single draft changeset shown

  $ echo 0 > foo
  $ hg -q commit -A -m 'commit 0'

  $ hg show work
  @  9f171 commit 0

Even when it isn't the wdir

  $ hg -q up null

  $ hg show work
  o  9f171 commit 0

Single changeset is still there when public because it is a head

  $ hg phase --public -r 0
  $ hg show work
  o  9f171 commit 0

A draft child will show both it and public parent

  $ hg -q up 0
  $ echo 1 > foo
  $ hg commit -m 'commit 1'

  $ hg show work
  @  181cc commit 1
  o  9f171 commit 0

Multiple draft children will be shown

  $ echo 2 > foo
  $ hg commit -m 'commit 2'

  $ hg show work
  @  128c8 commit 2
  o  181cc commit 1
  o  9f171 commit 0

Bumping first draft changeset to public will hide its parent

  $ hg phase --public -r 1
  $ hg show work
  @  128c8 commit 2
  o  181cc commit 1
  |
  ~

Multiple DAG heads will be shown

  $ hg -q up -r 1
  $ echo 3 > foo
  $ hg commit -m 'commit 3'
  created new head

  $ hg show work
  @  f0abc commit 3
  | o  128c8 commit 2
  |/
  o  181cc commit 1
  |
  ~

Even when wdir is something else

  $ hg -q up null

  $ hg show work
  o  f0abc commit 3
  | o  128c8 commit 2
  |/
  o  181cc commit 1
  |
  ~

Draft child shows public head (multiple heads)

  $ hg -q up 0
  $ echo 4 > foo
  $ hg commit -m 'commit 4'
  created new head

  $ hg show work
  @  668ca commit 4
  | o  f0abc commit 3
  | | o  128c8 commit 2
  | |/
  | o  181cc commit 1
  |/
  o  9f171 commit 0

  $ cd ..

Branch name appears in output

  $ hg init branches
  $ cd branches
  $ echo 0 > foo
  $ hg -q commit -A -m 'commit 0'
  $ echo 1 > foo
  $ hg commit -m 'commit 1'
  $ echo 2 > foo
  $ hg commit -m 'commit 2'
  $ hg phase --public -r .
  $ hg -q up -r 1
  $ hg branch mybranch
  marked working directory as branch mybranch
  (branches are permanent and global, did you want a bookmark?)
  $ echo 3 > foo
  $ hg commit -m 'commit 3'
  $ echo 4 > foo
  $ hg commit -m 'commit 4'

  $ hg show work
  @  f8dd3 (mybranch) commit 4
  o  90cfc (mybranch) commit 3
  | o  128c8 commit 2
  |/
  o  181cc commit 1
  |
  ~

  $ cd ..

Bookmark name appears in output

  $ hg init bookmarks
  $ cd bookmarks
  $ echo 0 > foo
  $ hg -q commit -A -m 'commit 0'
  $ echo 1 > foo
  $ hg commit -m 'commit 1'
  $ echo 2 > foo
  $ hg commit -m 'commit 2'
  $ hg phase --public -r .
  $ hg bookmark @
  $ hg -q up -r 1
  $ echo 3 > foo
  $ hg commit -m 'commit 3'
  created new head
  $ echo 4 > foo
  $ hg commit -m 'commit 4'
  $ hg bookmark mybook

  $ hg show work
  @  cac82 (mybook) commit 4
  o  f0abc commit 3
  | o  128c8 (@) commit 2
  |/
  o  181cc commit 1
  |
  ~

  $ cd ..

Tags are rendered

  $ hg init tags
  $ cd tags
  $ echo 0 > foo
  $ hg -q commit -A -m 'commit 1'
  $ echo 1 > foo
  $ hg commit -m 'commit 2'
  $ hg tag 0.1
  $ hg phase --public -r .
  $ echo 2 > foo
  $ hg commit -m 'commit 3'
  $ hg tag 0.2

  $ hg show work
  @  37582 Added tag 0.2 for changeset 6379c25b76f1
  o  6379c (0.2) commit 3
  o  a2ad9 Added tag 0.1 for changeset 6a75536ea0b1
  |
  ~

  $ cd ..

Multiple names on same changeset render properly

  $ hg init multiplenames
  $ cd multiplenames
  $ echo 0 > foo
  $ hg -q commit -A -m 'commit 1'
  $ hg phase --public -r .
  $ hg branch mybranch
  marked working directory as branch mybranch
  (branches are permanent and global, did you want a bookmark?)
  $ hg bookmark mybook
  $ echo 1 > foo
  $ hg commit -m 'commit 2'

  $ hg show work
  @  34834 (mybook) (mybranch) commit 2
  o  97fcc commit 1

Multiple bookmarks on same changeset render properly

  $ hg book mybook2
  $ hg show work
  @  34834 (mybook mybook2) (mybranch) commit 2
  o  97fcc commit 1

  $ cd ..

Extra namespaces are rendered

  $ hg init extranamespaces
  $ cd extranamespaces
  $ echo 0 > foo
  $ hg -q commit -A -m 'commit 1'
  $ hg phase --public -r .
  $ echo 1 > foo
  $ hg commit -m 'commit 2'
  $ echo 2 > foo
  $ hg commit -m 'commit 3'

  $ hg --config extensions.revnames=$TESTDIR/revnamesext.py show work
  @  32f3e (r2) commit 3
  o  6a755 (r1) commit 2
  o  97fcc (r0) commit 1

  $ cd ..