view tests/test-pull-update.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.

  $ hg init t
  $ cd t
  $ echo 1 > foo
  $ hg ci -Am m
  adding foo

  $ cd ..
  $ hg clone t tt
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd tt
  $ echo 1.1 > foo
  $ hg ci -Am m

  $ cd ../t
  $ echo 1.2 > foo
  $ hg ci -Am m

Should respect config to disable dirty update
  $ hg co -qC 0
  $ echo 2 > foo
  $ hg --config experimental.updatecheck=abort pull -u ../tt
  pulling from ../tt
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  abort: uncommitted changes
  [255]
  $ hg --config extensions.strip= strip --no-backup tip
  $ hg co -qC tip

Should not update to the other topological branch:

  $ hg pull -u ../tt
  pulling from ../tt
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  updated to "800c91d5bfc1: m"
  1 other heads for branch "default"

  $ cd ../tt

Should not update to the other branch:

  $ hg pull -u ../t
  pulling from ../t
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  updated to "107cefe13e42: m"
  1 other heads for branch "default"

  $ HGMERGE=true hg merge
  merging foo
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -mm

  $ cd ../t

Should work:

  $ hg pull -u ../tt
  pulling from ../tt
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (-1 heads)
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

Similarity between "hg update" and "hg pull -u" in handling bookmark
====================================================================

Test that updating activates the bookmark, which matches with the
explicit destination of the update.

  $ echo 4 >> foo
  $ hg commit -m "#4"
  $ hg bookmark active-after-pull
  $ cd ../tt

(1) activating by --rev BOOKMARK

  $ hg bookmark -f active-before-pull
  $ hg bookmarks
   * active-before-pull        3:483b76ad4309

  $ hg pull -u -r active-after-pull
  pulling from $TESTTMP/t (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  adding remote bookmark active-after-pull
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (activating bookmark active-after-pull)

  $ hg parents -q
  4:f815b3da6163
  $ hg bookmarks
   * active-after-pull         4:f815b3da6163
     active-before-pull        3:483b76ad4309

(discard pulled changes)

  $ hg update -q 483b76ad4309
  $ hg rollback -q

(2) activating by URL#BOOKMARK

  $ hg bookmark -f active-before-pull
  $ hg bookmarks
   * active-before-pull        3:483b76ad4309

  $ hg pull -u $TESTTMP/t#active-after-pull
  pulling from $TESTTMP/t (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  adding remote bookmark active-after-pull
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (activating bookmark active-after-pull)

  $ hg parents -q
  4:f815b3da6163
  $ hg bookmarks
   * active-after-pull         4:f815b3da6163
     active-before-pull        3:483b76ad4309

(discard pulled changes)

  $ hg update -q 483b76ad4309
  $ hg rollback -q

Test that updating deactivates current active bookmark, if the
destination of the update is explicitly specified, and it doesn't
match with the name of any existing bookmarks.

  $ cd ../t
  $ hg bookmark -d active-after-pull
  $ hg branch bar -q
  $ hg commit -m "#5 (bar #1)"
  $ cd ../tt

(1) deactivating by --rev REV

  $ hg bookmark -f active-before-pull
  $ hg bookmarks
   * active-before-pull        3:483b76ad4309

  $ hg pull -u -r b5e4babfaaa7
  pulling from $TESTTMP/t (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 1 changes to 1 files
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (leaving bookmark active-before-pull)

  $ hg parents -q
  5:b5e4babfaaa7
  $ hg bookmarks
     active-before-pull        3:483b76ad4309

(discard pulled changes)

  $ hg update -q 483b76ad4309
  $ hg rollback -q

(2) deactivating by --branch BRANCH

  $ hg bookmark -f active-before-pull
  $ hg bookmarks
   * active-before-pull        3:483b76ad4309

  $ hg pull -u -b bar
  pulling from $TESTTMP/t (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 1 changes to 1 files
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (leaving bookmark active-before-pull)

  $ hg parents -q
  5:b5e4babfaaa7
  $ hg bookmarks
     active-before-pull        3:483b76ad4309

(discard pulled changes)

  $ hg update -q 483b76ad4309
  $ hg rollback -q

(3) deactivating by URL#ANOTHER-BRANCH

  $ hg bookmark -f active-before-pull
  $ hg bookmarks
   * active-before-pull        3:483b76ad4309

  $ hg pull -u $TESTTMP/t#bar
  pulling from $TESTTMP/t (glob)
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 1 changes to 1 files
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (leaving bookmark active-before-pull)

  $ hg parents -q
  5:b5e4babfaaa7
  $ hg bookmarks
     active-before-pull        3:483b76ad4309

  $ cd ..