atomicupdate: add an experimental option to use atomictemp when updating
In some cases Mercurial truncating files when updating causes problems. It can
happens when processes are currently reading the file or with big file or on
NFS mounts.
We add an experimental option to use the atomictemp option of vfs.__call__ in
order to avoid the problem.
The localrepository.wwrite seems to assume the files are created without the
`x` flag; with atomictempfile, the new file might inherit the `x` flag from
the destination. We force remove it afterward. This code could be refactored
and the flag processing could be moved inside vfs.
This patch should be tested with
`--extra-config-opt experimental.update.atomic-file=True`
as we disabled the option by default.
Differential Revision: https://phab.mercurial-scm.org/D1882
#require execbit
b51a8138292a introduced a regression where we would mention in the
changelog executable files added by the second parent of a merge. Test
that that doesn't happen anymore
$ hg init repo
$ cd repo
$ echo foo > foo
$ hg ci -qAm 'add foo'
$ echo bar > bar
$ chmod +x bar
$ hg ci -qAm 'add bar'
manifest of p2:
$ hg manifest
bar
foo
$ hg up -qC 0
$ echo >> foo
$ hg ci -m 'change foo'
created new head
manifest of p1:
$ hg manifest
foo
$ hg merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ chmod +x foo
$ hg ci -m 'merge'
this should not mention bar but should mention foo:
$ hg tip -v
changeset: 3:c53d17ff3380
tag: tip
parent: 2:ed1b79f46b9a
parent: 1:d394a8db219b
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files: foo
description:
merge
$ hg debugindex bar
rev offset length ..... linkrev nodeid p1 p2 (re)
0 0 5 ..... 1 b004912a8510 000000000000 000000000000 (re)
$ cd ..