dirstate: set identity whenever we read the dirstate's v2 docket
The docket can be loaded outside of a full read (for exemple when
pre-fetching parents), so the current code would read/set the identity
after loading the data, opening a race condition:
A0: first process docket is read
B0: other process appends new data to the dirstate (and changes the docket)
A1: first process sets the identity (based on pre-B content, but with post-B identity)
A1: first process loads the dirstatemap from the data file
A1: first process does not detect the race and overwrites the update from B.
==========================================================
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 experimental.revlogv2=enable-unstable-format-and-corrupt-my-data
$ 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
$ hg debug-revlog-index --verbose -c
rev rank linkrev nodeid p1-rev p1-nodeid p2-rev p2-nodeid full-size delta-base flags comp-mode data-offset chunk-size sd-comp-mode sidedata-offset sd-chunk-size
0 -1 0 7049e48789d7 -1 000000000000 -1 000000000000 54 0 0 0 0 54 plain 0 90
1 -1 1 2707720c6597 0 7049e48789d7 -1 000000000000 54 1 0 0 54 54 plain 90 90
2 -1 2 40f977031323 1 2707720c6597 -1 000000000000 55 2 0 0 108 55 plain 180 90
$ hg debug-revlog-index --verbose -m
rev rank linkrev nodeid p1-rev p1-nodeid p2-rev p2-nodeid full-size delta-base flags comp-mode data-offset chunk-size sd-comp-mode sidedata-offset sd-chunk-size
0 -1 0 b85d294330e3 -1 000000000000 -1 000000000000 43 0 0 0 0 43 plain 0 90
1 -1 1 1a0aec305c63 0 b85d294330e3 -1 000000000000 86 0 0 0 43 55 plain 90 90
2 -1 2 104258a4f75f 1 1a0aec305c63 -1 000000000000 86 1 0 0 98 55 plain 180 90
Check upgrade behavior
======================
Right now, sidedata has not upgrade support
Check that we can upgrade to sidedata
-------------------------------------
$ hg init up-no-side-data --config experimental.revlogv2=no
$ hg debugformat -v -R up-no-side-data | egrep 'changelog-v2|revlog-v2'
revlog-v2: no no no
changelog-v2: no no no
$ hg debugformat -v -R up-no-side-data --config experimental.revlogv2=enable-unstable-format-and-corrupt-my-data | egrep 'changelog-v2|revlog-v2'
revlog-v2: no yes no
changelog-v2: no no no
$ hg debugupgraderepo -R up-no-side-data --config experimental.revlogv2=enable-unstable-format-and-corrupt-my-data > /dev/null
Check that we can downgrade from sidedata
-----------------------------------------
$ hg init up-side-data --config experimental.revlogv2=enable-unstable-format-and-corrupt-my-data
$ hg debugformat -v -R up-side-data | egrep 'changelog-v2|revlog-v2'
revlog-v2: yes no no
changelog-v2: no no no
$ hg debugformat -v -R up-side-data --config experimental.revlogv2=no | egrep 'changelog-v2|revlog-v2'
revlog-v2: yes no no
changelog-v2: no no no
$ hg debugupgraderepo -R up-side-data --config experimental.revlogv2=no > /dev/null