view tests/test-update-atomic.t @ 44996:c2df0bca0dfa

perf: make `hg perfwrite` more flexible

The more flexible command was used recently while finding a solution for a
buffering bug (eventually fixed in f9734b2d59cc (the changeset description uses
a different benchmark)).

In comparison to the previous version, the new version is much more flexible.
While using it, the focus was on testing small writes. For this reason, by
default it calls ui.write() 100 times with a single byte plus one newline byte,
for 100 lines.

To get the previous behavior, run `hg perfwrite --nlines=100000 --nitems=1
--item='Testing write performance' --batch-line`.

#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