vfs: use checkambigatclosing in checkambig=True but atomictemp=False case
In Mercurial source tree, opening a file in "a"/"a+" mode like below
doesn't specify atomictemp=True for vfs, and this avoids file stat
ambiguity check by atomictempfile.
- writing changes out in revlog layer uses "a+" mode
- truncation in repair.strip() uses "a" mode
- truncation in transaction._playback() uses "a" mode
If steps below occurs at "the same time in sec", all of mtime, ctime
and size are same between (1) and (3).
1. append data to revlog-style file (and close transaction)
2. discard appended data by truncation (strip or rollback)
3. append same size but different data to revlog-style file again
Therefore, cache validation doesn't work after (3) as expected.
This patch uses checkambigatclosing in checkambig=True but
atomictemp=False case, to check (and get rid of) file stat ambiguity
at closing.
This is a part of ExactCacheValidationPlan.
https://www.mercurial-scm.org/wiki/ExactCacheValidationPlan
#require docutils
#require gettext
Test document extraction
$ HGENCODING=UTF-8
$ export HGENCODING
$ { echo C; ls "$TESTDIR/../i18n"/*.po | sort; } | while read PO; do
> LOCALE=`basename "$PO" .po`
> echo "% extracting documentation from $LOCALE"
> LANGUAGE=$LOCALE python "$TESTDIR/../doc/gendoc.py" >> gendoc-$LOCALE.txt 2> /dev/null || exit
>
> if [ $LOCALE != C ]; then
> if [ ! -f $TESTDIR/test-gendoc-$LOCALE.t ]; then
> echo missing test-gendoc-$LOCALE.t
> fi
> cmp -s gendoc-C.txt gendoc-$LOCALE.txt && echo "** NOTHING TRANSLATED ($LOCALE) **"
> fi
> done; true
% extracting documentation from C
% extracting documentation from da
% extracting documentation from de
% extracting documentation from el
% extracting documentation from fr
% extracting documentation from it
% extracting documentation from ja
% extracting documentation from pt_BR
% extracting documentation from ro
% extracting documentation from ru
% extracting documentation from sv
% extracting documentation from zh_CN
% extracting documentation from zh_TW