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 killdaemons
= Test the known() protocol function =
Create a test repository:
$ hg init repo
$ cd repo
$ touch a ; hg add a ; hg ci -ma
$ touch b ; hg add b ; hg ci -mb
$ touch c ; hg add c ; hg ci -mc
$ hg log --template '{node}\n'
991a3460af53952d10ec8a295d3d2cc2e5fa9690
0e067c57feba1a5694ca4844f05588bb1bf82342
3903775176ed42b1458a6281db4a0ccf4d9f287a
$ cd ..
Test locally:
$ hg debugknown repo 991a3460af53952d10ec8a295d3d2cc2e5fa9690 0e067c57feba1a5694ca4844f05588bb1bf82342 3903775176ed42b1458a6281db4a0ccf4d9f287a
111
$ hg debugknown repo 000a3460af53952d10ec8a295d3d2cc2e5fa9690 0e067c57feba1a5694ca4844f05588bb1bf82342 0003775176ed42b1458a6281db4a0ccf4d9f287a
010
$ hg debugknown repo
Test via HTTP:
$ hg serve -R repo -p $HGPORT -d --pid-file=hg.pid -E error.log -A access.log
$ cat hg.pid >> $DAEMON_PIDS
$ hg debugknown http://localhost:$HGPORT/ 991a3460af53952d10ec8a295d3d2cc2e5fa9690 0e067c57feba1a5694ca4844f05588bb1bf82342 3903775176ed42b1458a6281db4a0ccf4d9f287a
111
$ hg debugknown http://localhost:$HGPORT/ 000a3460af53952d10ec8a295d3d2cc2e5fa9690 0e067c57feba1a5694ca4844f05588bb1bf82342 0003775176ed42b1458a6281db4a0ccf4d9f287a
010
$ hg debugknown http://localhost:$HGPORT/
$ cat error.log
$ killdaemons.py