tests/test-dirstate.t

merge: cache unknown dir checks (issue5716)

As mentioned in D1222, the recent pathconflicts change regresses update
performance in large repositories when many files are being updated.

To mitigate this, we introduce two caches of directories that have
already found to be either:

  - unknown directories, but which are not aliased by files and
    so don't need to be checked if they are files again; and

  - missing directores, which cannot cause path conflicts, and
    cannot contain a file that causes a path conflict.

When checking the paths of a file, testing against this caches means we can
skip tests that involve touching the filesystem.

Differential Revision: https://phab.mercurial-scm.org/D1224

------ Test dirstate._dirs refcounting

  $ hg init t
  $ cd t
  $ mkdir -p a/b/c/d
  $ touch a/b/c/d/x
  $ touch a/b/c/d/y
  $ touch a/b/c/d/z
  $ hg ci -Am m
  adding a/b/c/d/x
  adding a/b/c/d/y
  adding a/b/c/d/z
  $ hg mv a z
  moving a/b/c/d/x to z/b/c/d/x (glob)
  moving a/b/c/d/y to z/b/c/d/y (glob)
  moving a/b/c/d/z to z/b/c/d/z (glob)

Test name collisions

  $ rm z/b/c/d/x
  $ mkdir z/b/c/d/x
  $ touch z/b/c/d/x/y
  $ hg add z/b/c/d/x/y
  abort: file 'z/b/c/d/x' in dirstate clashes with 'z/b/c/d/x/y'
  [255]
  $ rm -rf z/b/c/d
  $ touch z/b/c/d
  $ hg add z/b/c/d
  abort: directory 'z/b/c/d' already in dirstate
  [255]

  $ cd ..

Issue1790: dirstate entry locked into unset if file mtime is set into
the future

Prepare test repo:

  $ hg init u
  $ cd u
  $ echo a > a
  $ hg add
  adding a
  $ hg ci -m1

Set mtime of a into the future:

  $ touch -t 202101011200 a

Status must not set a's entry to unset (issue1790):

  $ hg status
  $ hg debugstate
  n 644          2 2021-01-01 12:00:00 a

Test modulo storage/comparison of absurd dates:

#if no-aix
  $ touch -t 195001011200 a
  $ hg st
  $ hg debugstate
  n 644          2 2018-01-19 15:14:08 a
#endif

Verify that exceptions during a dirstate change leave the dirstate
coherent (issue4353)

  $ cat > ../dirstateexception.py <<EOF
  > from __future__ import absolute_import
  > from mercurial import (
  >   error,
  >   extensions,
  >   merge,
  > )
  > 
  > def wraprecordupdates(orig, repo, actions, branchmerge):
  >     raise error.Abort("simulated error while recording dirstateupdates")
  > 
  > def reposetup(ui, repo):
  >     extensions.wrapfunction(merge, 'recordupdates', wraprecordupdates)
  > EOF

  $ hg rm a
  $ hg commit -m 'rm a'
  $ echo "[extensions]" >> .hg/hgrc
  $ echo "dirstateex=../dirstateexception.py" >> .hg/hgrc
  $ hg up 0
  abort: simulated error while recording dirstateupdates
  [255]
  $ hg log -r . -T '{rev}\n'
  1
  $ hg status
  ? a