revlogv2: track pending write in the docket and expose it to hooks
The docket is now able to write pending data. We could have used a distinct
intermediate files, however keeping everything in the same file will make it
simpler to keep track of the various involved files if necessary.
However it might prove more complicated for streaming clone. This will be dealt
with later.
Note that we lifted the stderr redirection in the test since we no longer suffer
from "unkown working directory parent" message.
Differential Revision: https://phab.mercurial-scm.org/D10631
#require execbit unix-permissions no-chg
Checking that experimental.atomic-file works.
$ cat > $TESTTMP/show_mode.py <<EOF
> from __future__ import print_function
> import os
> import stat
> import sys
> ST_MODE = stat.ST_MODE
>
> for file_path in sys.argv[1:]:
> file_stat = os.stat(file_path)
> octal_mode = oct(file_stat[ST_MODE] & 0o777).replace('o', '')
> print("%s:%s" % (file_path, octal_mode))
>
> EOF
$ hg init repo
$ cd repo
$ cat > .hg/showwrites.py <<EOF
> from __future__ import print_function
> from mercurial import pycompat
> from mercurial.utils import stringutil
> def uisetup(ui):
> from mercurial import vfs
> class newvfs(vfs.vfs):
> def __call__(self, *args, **kwargs):
> print(pycompat.sysstr(stringutil.pprint(
> ('vfs open', args, sorted(list(kwargs.items()))))))
> return super(newvfs, self).__call__(*args, **kwargs)
> vfs.vfs = newvfs
> EOF
$ for v in a1 a2 b1 b2 c ro; do echo $v > $v; done
$ chmod +x b*
$ hg commit -Aqm _
# We check that
# - the changes are actually atomic
# - that permissions are correct (all 4 cases of (executable before) * (executable after))
# - that renames work, though they should be atomic anyway
# - that it works when source files are read-only (but directories are read-write still)
$ for v in a1 a2 b1 b2 ro; do echo changed-$v > $v; done
$ chmod -x *1; chmod +x *2
$ hg rename c d
$ hg commit -qm _
Check behavior without update.atomic-file
$ hg update -r 0 -q
$ hg update -r 1 --config extensions.showwrites=.hg/showwrites.py 2>&1 | grep "a1'.*wb"
('vfs open', ('a1', 'wb'), [('atomictemp', False), ('backgroundclose', True)])
$ "$PYTHON" $TESTTMP/show_mode.py *
a1:0644
a2:0755
b1:0644
b2:0755
d:0644
ro:0644
Add a second revision for the ro file so we can test update when the file is
present or not
$ echo "ro" > ro
$ hg commit -qm _
Check behavior without update.atomic-file first
$ hg update -C -r 0 -q
$ hg update -r 1
6 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ "$PYTHON" $TESTTMP/show_mode.py *
a1:0644
a2:0755
b1:0644
b2:0755
d:0644
ro:0644
Manually reset the mode of the read-only file
$ chmod a-w ro
$ "$PYTHON" $TESTTMP/show_mode.py ro
ro:0444
Now the file is present, try to update and check the permissions of the file
$ hg up -r 2
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ "$PYTHON" $TESTTMP/show_mode.py ro
ro:0644
# The file which was read-only is now writable in the default behavior
Check behavior with update.atomic-files
$ cat >> .hg/hgrc <<EOF
> [experimental]
> update.atomic-file = true
> EOF
$ hg update -C -r 0 -q
$ hg update -r 1 --config extensions.showwrites=.hg/showwrites.py 2>&1 | grep "a1'.*wb"
('vfs open', ('a1', 'wb'), [('atomictemp', True), ('backgroundclose', True)])
$ hg st -A --rev 1
C a1
C a2
C b1
C b2
C d
C ro
Check the file permission after update
$ "$PYTHON" $TESTTMP/show_mode.py *
a1:0644
a2:0755
b1:0644
b2:0755
d:0644
ro:0644
Manually reset the mode of the read-only file
$ chmod a-w ro
$ "$PYTHON" $TESTTMP/show_mode.py ro
ro:0444
Now the file is present, try to update and check the permissions of the file
$ hg update -r 2 --traceback
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ "$PYTHON" $TESTTMP/show_mode.py ro
ro:0644
# The behavior is the same as without atomic update