view tests/test-sidedata.t @ 47072:4c041c71ec01

revlog: introduce an explicit tracking of what the revlog is about

Since the dawn of time, people have been forced to rely to lossy introspection
of the index filename to determine what the purpose and role of the revlog they
encounter is. This is hacky, error prone, inflexible, abstraction-leaky,
<insert-your-own-complaints-here>.

In f63299ee7e4d Raphaël introduced a new attribute to track this information:
`revlog_kind`. However it is initialized in an odd place and various instances
end up not having it set. In addition is only tracking some of the information
we end up having to introspect in various pieces of code.

So we add a new attribute that holds more data and is more strictly enforced.
This work is done in collaboration with Raphaël.

The `revlog_kind` one will be removed/adapted in the next changeset. We expect
to be able to clean up various existing piece of code and to simplify coming
work around the newer revlog format.

Differential Revision: https://phab.mercurial-scm.org/D10352

==========================================================
Test file dedicated to checking side-data related behavior
==========================================================

Check data can be written/read from sidedata
============================================

  $ cat << EOF >> $HGRCPATH
  > [extensions]
  > testsidedata=$TESTDIR/testlib/ext-sidedata.py
  > EOF

  $ hg init test-sidedata --config format.exp-use-side-data=yes
  $ cd test-sidedata
  $ echo aaa > a
  $ hg add a
  $ hg commit -m a --traceback
  $ echo aaa > b
  $ hg add b
  $ hg commit -m b
  $ echo xxx >> a
  $ hg commit -m aa

  $ hg debugsidedata -c 0
  2 sidedata entries
   entry-0001 size 4
   entry-0002 size 32
  $ hg debugsidedata -c 1 -v
  2 sidedata entries
   entry-0001 size 4
    '\x00\x00\x006'
   entry-0002 size 32
    '\x98\t\xf9\xc4v\xf0\xc5P\x90\xf7wRf\xe8\xe27e\xfc\xc1\x93\xa4\x96\xd0\x1d\x97\xaaG\x1d\xd7t\xfa\xde'
  $ hg debugsidedata -m 2
  2 sidedata entries
   entry-0001 size 4
   entry-0002 size 32
  $ hg debugsidedata a  1
  2 sidedata entries
   entry-0001 size 4
   entry-0002 size 32

Check upgrade behavior
======================

Right now, sidedata has not upgrade support

Check that we can upgrade to sidedata
-------------------------------------

  $ hg init up-no-side-data --config format.exp-use-side-data=no
  $ hg debugformat -v -R up-no-side-data
  format-variant     repo config default
  fncache:            yes    yes     yes
  dotencode:          yes    yes     yes
  generaldelta:       yes    yes     yes
  share-safe:          no     no      no
  sparserevlog:       yes    yes     yes
  persistent-nodemap:  no     no      no (no-rust !)
  persistent-nodemap: yes    yes      no (rust !)
  copies-sdc:          no     no      no
  revlog-v2:           no     no      no
  plain-cl-delta:     yes    yes     yes
  compression:        zlib   zlib    zlib (no-zstd !)
  compression:        zstd   zstd    zstd (zstd !)
  compression-level:  default default default
  $ hg debugformat -v -R up-no-side-data --config format.exp-use-side-data=yes
  format-variant     repo config default
  fncache:            yes    yes     yes
  dotencode:          yes    yes     yes
  generaldelta:       yes    yes     yes
  share-safe:          no     no      no
  sparserevlog:       yes    yes     yes
  persistent-nodemap:  no     no      no (no-rust !)
  persistent-nodemap: yes    yes      no (rust !)
  copies-sdc:          no     no      no
  revlog-v2:           no    yes      no
  plain-cl-delta:     yes    yes     yes
  compression:        zlib   zlib    zlib (no-zstd !)
  compression:        zstd   zstd    zstd (zstd !)
  compression-level:  default default default
  $ hg debugupgraderepo -R up-no-side-data --config format.exp-use-side-data=yes > /dev/null

Check that we can downgrade from sidedata
-----------------------------------------

  $ hg init up-side-data --config format.exp-use-side-data=yes
  $ hg debugformat -v -R up-side-data
  format-variant     repo config default
  fncache:            yes    yes     yes
  dotencode:          yes    yes     yes
  generaldelta:       yes    yes     yes
  share-safe:          no     no      no
  sparserevlog:       yes    yes     yes
  persistent-nodemap:  no     no      no (no-rust !)
  persistent-nodemap: yes    yes      no (rust !)
  copies-sdc:          no     no      no
  revlog-v2:          yes     no      no
  plain-cl-delta:     yes    yes     yes
  compression:        zlib   zlib    zlib (no-zstd !)
  compression:        zstd   zstd    zstd (zstd !)
  compression-level:  default default default
  $ hg debugformat -v -R up-side-data --config format.exp-use-side-data=no
  format-variant     repo config default
  fncache:            yes    yes     yes
  dotencode:          yes    yes     yes
  generaldelta:       yes    yes     yes
  share-safe:          no     no      no
  sparserevlog:       yes    yes     yes
  persistent-nodemap:  no     no      no (no-rust !)
  persistent-nodemap: yes    yes      no (rust !)
  copies-sdc:          no     no      no
  revlog-v2:          yes     no      no
  plain-cl-delta:     yes    yes     yes
  compression:        zlib   zlib    zlib (no-zstd !)
  compression:        zstd   zstd    zstd (zstd !)
  compression-level:  default default default
  $ hg debugupgraderepo -R up-side-data --config format.exp-use-side-data=no > /dev/null