view tests/test-basic.t @ 24787:9d5c27890790

largefiles: for update -C, only update largefiles when necessary

Before, a --clean update with largefiles would use the "optimization" that it
didn't read hashes from standin files before and after the update. Instead of
trusting the content of the standin files, it would rehash all the actual
largefiles that lfdirstate reported clean and update the standins that didn't
have the expected content. It could thus in some "impossible" situations
automatically recover from some "largefile got out sync with its standin"
issues (even there apparently still were weird corner cases where it could
fail). This extra checking is similar to what core --clean intentionally do
not do, and it made update --clean unbearable slow.

Usually in core Mercurial, --clean will rely on the dirstate to find the files
it should update. (It is thus intentionally possible (when trying to trick the
system or if there should be bugs) to end up in situations where --clean not
will restore the working directory content correctly.) Checking every file when
we "know" it is ok is however not an option - that would be too slow.

Instead, trust the content of the standin files. Use the same logic for --clean
as for linear updates and trust the dirstate and that our "logic" will keep
them in sync. It is much cheaper to just rehash the largefiles reported dirty
by a status walk and read all standins than to hash largefiles.

Most of the changes are just a change of indentation now when the different
kinds of updates no longer are handled that differently. Standins for added
files are however only written when doing a normal update, while deleted and
removed files only will be updated for --clean updates.

Create a repository:

  $ hg config
  defaults.backout=-d "0 0"
  defaults.commit=-d "0 0"
  defaults.shelve=--date "0 0"
  defaults.tag=-d "0 0"
  devel.all=true
  largefiles.usercache=$TESTTMP/.cache/largefiles (glob)
  ui.slash=True
  ui.interactive=False
  ui.mergemarkers=detailed
  ui.promptecho=True
  $ hg init t
  $ cd t

Make a changeset:

  $ echo a > a
  $ hg add a
  $ hg commit -m test

This command is ancient:

  $ hg history
  changeset:   0:acb14030fe0a
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     test
  

Verify that updating to revision 0 via commands.update() works properly

  $ cat <<EOF > update_to_rev0.py
  > from mercurial import ui, hg, commands
  > myui = ui.ui()
  > repo = hg.repository(myui, path='.')
  > commands.update(myui, repo, rev=0)
  > EOF
  $ hg up null
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ python ./update_to_rev0.py
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg identify -n
  0


Poke around at hashes:

  $ hg manifest --debug
  b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 644   a

  $ hg cat a
  a

Verify should succeed:

  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  1 files, 1 changesets, 1 total revisions

At the end...

  $ cd ..