revlog: add a callback "tracking" duplicate node addition
If a changegroup contains node already added to the repository, they will be
skipped. Skipping them is the right behavior (we don't need to store things
twice), but it can hide some information to the code doing the unbundle (eg:
shelve looking for the tip of the bundle).
The first step to improve this situation is to add a low level callback. We do
not need this tracking on all revlog, so actual tracking will be added in the
next changeset.
#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 empty-repo
$ cd empty-repo
$ cat .hg/requires
dotencode
exp-revlogv2.0
fncache
store
$ hg log
Unknown flags to revlog are rejected
>>> with open('.hg/store/00changelog.i', 'wb') as fh:
... fh.write(b'\x00\x04\xde\xad') and None
$ hg log
abort: unknown flags (0x04) in version 57005 revlog 00changelog.i!
[255]
$ 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 (changelog always disables generaldelta)
$ f --hexdump --bytes 4 .hg/store/00changelog.i
.hg/store/00changelog.i:
0000: 00 01 de ad |....|
$ f --hexdump --bytes 4 .hg/store/data/foo.i
.hg/store/data/foo.i:
0000: 00 03 de ad |....|