view tests/test-revlog-v2.t @ 47682:78f7f0d490ee

dirstate-v2: Move fixed-size tree metadata into the docket file

Before this changeset, the dirstate-v2 data file contained not only nodes
and paths that may be reused when appending to an existing file,
but also some fixed-size metadata that applies to the entire tree
and was added at the end of the data file for every append.

This moves that metadata into the docket file, so that repeated "append"
operations without meaningful changes don’t actually need to grow any file.

Differential Revision: https://phab.mercurial-scm.org/D11098

#require reporevlogstore

A repo with unknown revlogv2 requirement string cannot be opened

  $ hg init invalidreq
  $ cd invalidreq
  $ echo exp-revlogv2.unknown >> .hg/requires
  $ hg log
  abort: repository requires features unknown to this Mercurial: exp-revlogv2.unknown
  (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
  [255]
  $ cd ..

Can create and open repo with revlog v2 requirement

  $ cat >> $HGRCPATH << EOF
  > [experimental]
  > revlogv2 = enable-unstable-format-and-corrupt-my-data
  > EOF

  $ hg init new-repo
  $ cd new-repo
  $ cat .hg/requires
  dotencode
  exp-dirstate-v2 (dirstate-v2 !)
  exp-revlogv2.2
  fncache
  generaldelta
  persistent-nodemap (rust !)
  revlog-compression-zstd (zstd !)
  sparserevlog
  store

  $ hg log

Unknown flags to revlog are rejected

  >>> with open('.hg/store/00changelog.i', 'wb') as fh:
  ...     fh.write(b'\xff\x00\xde\xad') and None

  $ hg log
  abort: unknown flags (0xff00) in version 57005 revlog 00changelog
  [50]

  $ cd ..

Writing a simple revlog v2 works

  $ hg init simple
  $ cd simple
  $ touch foo
  $ hg -q commit -A -m initial

  $ hg log
  changeset:   0:96ee1d7354c4
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     initial
  

Header written as expected

  $ f --hexdump --bytes 4 .hg/store/00changelog.i
  .hg/store/00changelog.i:
  0000: 00 00 de ad                                     |....|

  $ f --hexdump --bytes 4 .hg/store/data/foo.i
  .hg/store/data/foo.i:
  0000: 00 00 de ad                                     |....|

Bundle use a compatible changegroup format
------------------------------------------

  $ hg bundle --all ../basic.hg
  1 changesets found
  $ hg debugbundle --spec ../basic.hg
  bzip2-v2

The expected files are generated
--------------------------------

We should have have:
- a docket
- a index file with a unique name
- a data file

  $ ls .hg/store/00changelog* .hg/store/00manifest*
  .hg/store/00changelog-1335303a.sda
  .hg/store/00changelog-6b8ab34b.idx
  .hg/store/00changelog-b875dfc5.dat
  .hg/store/00changelog.i
  .hg/store/00manifest-05a21d65.idx
  .hg/store/00manifest-43c37dde.dat
  .hg/store/00manifest-e2c9362a.sda
  .hg/store/00manifest.i

Local clone works
-----------------

  $ hg clone . ../cloned-repo
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg tip | tee ../tip-new
  changeset:   0:96ee1d7354c4
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     initial
  
  $ hg tip -R ../cloned-repo | tee ../tip-cloned
  changeset:   0:96ee1d7354c4
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     initial
  

The two repository should be identical, this diff MUST be empty

  $ cmp ../tip-new ../tip-cloned || diff -U8 ../tip-new ../tip-cloned


hg verify should be happy
-------------------------

  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  checked 1 changesets with 1 changes to 1 files

  $ hg verify -R ../cloned-repo
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  checked 1 changesets with 1 changes to 1 files