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
====================================
Testing head checking code: Case B-4
====================================
Mercurial checks for the introduction of new heads on push. Evolution comes
into play to detect if existing branches on the server are being replaced by
some of the new one we push.
This case is part of a series of tests checking this behavior.
Category B: simple case involving pruned changesets
TestCase 4: multi-changeset branch, all are pruned
.. old-state:
..
.. * 2 changeset branch
..
.. new-state:
..
.. * old branch is pruned
..
.. expected-result:
..
.. * push allowed
..
.. graph-summary:
..
.. B ⊗
.. |
.. A ⊗
.. |
.. | ◔ C
.. |/
.. ●
$ . $TESTDIR/testlib/push-checkheads-util.sh
Test setup
----------
$ mkdir B4
$ cd B4
$ setuprepos
creating basic server and client repo
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd server
$ mkcommit B0
$ cd ../client
$ hg pull
pulling from $TESTTMP/B4/server
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets d73caddc5533
(run 'hg update' to get a working copy)
$ hg up 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkcommit C0
created new head
$ hg debugobsolete --record-parents `getid "desc(A0)"`
obsoleted 1 changesets
1 new orphan changesets
$ hg debugobsolete --record-parents `getid "desc(B0)"`
obsoleted 1 changesets
$ hg log -G --hidden
@ 0f88766e02d6 (draft): C0
|
| x d73caddc5533 (draft): B0
| |
| x 8aaa48160adc (draft): A0
|/
o 1e4be0697311 (public): root
Actual testing
--------------
$ hg push
pushing to $TESTTMP/B4/server
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
2 new obsolescence markers
obsoleted 2 changesets
$ cd ../..