revert: do not reverse hunks in interactive when REV is not parent (issue5096)
And introduce a new "apply" operation verb for this case as suggested in
issue5096. This replaces the no longer used "revert" operation.
In interactive revert, when reverting to something else that the parent
revision, display an "apply this change" message with a diff that is not
reversed.
The rationale is that `hg revert -i -r REV` will show hunks of the diff from
the working directory to REV and prompt the user to select them for applying
(to working directory). This contradicts dcc56e10c23b in which it was
decided to have the "direction" of prompted hunks reversed. Later on
[1], there was a broad consensus (but no decision) towards the "as to
be applied direction". Now that --interactive is no longer experimental
(5910db5d1913), it's time to switch and thus we drop no longer used
"experimental.revertalternateinteractivemode" configuration option.
[1]: https://www.mercurial-scm.org/pipermail/mercurial-devel/2016-November/090142.html
.. feature::
When interactive revert is run against a revision other than the working
directory parent, the diff shown is the diff to *apply* to the working directory,
rather than the diff to *discard* from the working copy. This is in line with
related user experiences with `git` and appears to be less confusing with
`ui.interface=curses`.
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('\x00\x04\xde\xad')
$ 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 |....|