tests/test-mq-subrepo-svn.t

changelog: specify checkambig=True to revlog.__init__, to avoid ambiguity

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 00changelog.i (and close transaction)
  2. discard appended data by truncation (strip or rollback)
  3. append same size but different data to 00changelog.i again

Therefore, cache validation doesn't work after (3) as expected.

To avoid such file stat ambiguity around truncation, this patch
specifies checkambig=True to revlog.__init__(). This makes revlog
write changes out with checkambig=True.

Even though changes of 00changelog.i themselves are written out at
changelog._finalize(), this checkambig=True is needed, because
revlog.checkinlinesize(), which is invoked at the end of
changelog._finalize(), might replace already changed 00changelog.i by
converted one.

Even after this patch, avoiding file stat ambiguity of 00changelog.i
around truncation isn't yet completed, because truncation side isn't
aware of this issue.

This is a part of ExactCacheValidationPlan.

    https://www.mercurial-scm.org/wiki/ExactCacheValidationPlan

#require svn13

  $ cat <<EOF >> $HGRCPATH
  > [extensions]
  > mq =
  > [diff]
  > nodates = 1
  > EOF

fn to create new repository, and cd into it
  $ mkrepo() {
  >     hg init $1
  >     cd $1
  >     hg qinit
  > }


handle svn subrepos safely

  $ svnadmin create svn-repo-2499

  $ SVNREPOPATH=`pwd`/svn-repo-2499/project
#if windows
  $ SVNREPOURL=file:///`$PYTHON -c "import urllib, sys; sys.stdout.write(urllib.quote(sys.argv[1]))" "$SVNREPOPATH"`
#else
  $ SVNREPOURL=file://`$PYTHON -c "import urllib, sys; sys.stdout.write(urllib.quote(sys.argv[1]))" "$SVNREPOPATH"`
#endif

  $ mkdir -p svn-project-2499/trunk
  $ svn import -qm 'init project' svn-project-2499 "$SVNREPOURL"

qnew on repo w/svn subrepo
  $ mkrepo repo-2499-svn-subrepo
  $ svn co "$SVNREPOURL"/trunk sub
  Checked out revision 1.
  $ echo 'sub = [svn]sub' >> .hgsub
  $ hg add .hgsub
  $ hg status -S -X '**/format'
  A .hgsub
  $ hg qnew -m0 0.diff
  $ cd sub
  $ echo a > a
  $ svn add a
  A         a
  $ svn st
  A*    a (glob)
  $ cd ..
  $ hg status -S        # doesn't show status for svn subrepos (yet)
  $ hg qnew -m1 1.diff
  abort: uncommitted changes in subrepository 'sub'
  [255]

  $ cd ..