annotate: increase refcount of each revisions correctly (issue3841) Before this patch, refcount (managed in "needed") of parents of each revisions in "visit" is increased, only when parent is not annotated yet (examined by "p not in hist"). But this causes less refcount of the revision like "A" in the tree below ("A" is assumed as the second parent of "C"): A --- B --- C \ / \-----/ Steps of annotation for "C" in this case are shown below: 1. for "C" 1.1 increase refcount of "B" 1.2 increase refcount of "A" (=> 1) 1.3 defer annotation for "C" 2. for "A" 2.1 annotate for "A" (=> put result into "hist[A]") 2.2 clear "pcache[A]" ("pcache[A] = []") 3. for "B" 3.1 not increase refcount of "A", because "A not in hist" is False 3.2 annotate for "B" 3.3 decrease refcount of "A" (=> 0) 3.4 delete "hist[A]", even though "A" is still needed by "C" 3.5 clear "pcache[B]" 4. for "C", again 4.1 not increase refcount of "B", because "B not in hist" is False 4.2 increase refcount of "A" (=> 1) 4.3 defer annotation for "C" 5. for "A", again 5.1 annotate for "A" (=> put result into "hist[A]", again) 5.2 clear "pcache[A]" 6. for "C", once again 6.1 not increase refcount of "B", because "B not in hist" is False 6.2 not increase refcount of "A", because "A not in hist" is False 6.3 annotate for "C" 6.4 decrease refcount of "A", and delete "hist[A]" 6.5 decrease refcount of "B", and delete "hist[B]" 6.6 clear "pcache[C]" At step (5.1), annotation for "A" mis-recognizes that all lines are created at "A", because "pcache[A]" already cleared at step (2.2) prevents from scanning ancestors of "A". So, annotation for "C" or its descendants loses information about "A" or its ancestors. The root cause of this problem is that refcount of "A" is decreased at step (3.3), even though it isn't increased at step (3.1). To increase refcount correctly, this patch increases refcount of each parents of each revisions: - regardless of "p not in hist" or not, and - only once for each revisions in "visit" (by "not pcached") In fact, this problem should occur only on legacy repositories in which a filelog includes the merging between the revision and its ancestor (as the second parent), because: - tree is scanned in depth-first without such merging, revisions in "visit" refer different revisions as parent each other - recent Mercurial doesn't allow such merging changelog and manifest can include such merging someway, but filelogs can't, because "localrepository._filecommit()" converts such merging request to linear history. This patch tests merging cases below: these cases are from filelog of "mercurial/commands.py" in the repository of Mercurial itself. - both parents are same 10 --- 11 --- 12 \_/ filelogrev: changesetid: 10 00ea3613f82c 11 fc4a6e5b5812 12 4f802588cdfb - the second parent is also ancestor of the first one 37 --- 38 --- 39 --- 40 \________/ filelogrev: changesetid: 37 f8d56da6ac8f 38 38919e1c254d 39 d3400605d246 40 f06a4a3b86a7

Verify that pending changesets are seen by pretxn* hooks but not by other
processes that access the destination repo while the hooks are running.

The hooks (python and external) both reject changesets after some think time,
during which another process runs pull.  Each hook creates a file ('notify') to
indicate to the controlling process that it is running; the process removes the
file to indicate the hook can terminate.

init env vars

  $ d=`pwd`
  $ maxwait=20

utility to run the test - start a push in the background and run pull

  $ dotest() {
  >     rm -f notify
  >     printf 'push '; hg -R child-push tip --template '{node}\n'
  >     hg -R child-push -q push > push.out 2>&1 &
  > 
  >     # wait for hook to create the notify file
  >     i=$maxwait
  >     while [ ! -f notify -a $i != 0 ]; do
  >         sleep 1
  >         i=`expr $i - 1`
  >     done
  > 
  >     # run pull
  >     hg -R child-pull -q pull
  >     rc=$?
  > 
  >     # tell hook to finish; notify should exist.
  >     rm notify
  >     wait
  > 
  >     cat push.out
  >     printf 'pull '; hg -R child-pull tip --template '{node}\n'
  >     return $rc
  > }

python hook

  $ cat <<EOF > reject.py
  > import os, time
  > from mercurial import ui, localrepo
  > def rejecthook(ui, repo, hooktype, node, **opts):
  >     ui.write('hook %s\\n' % repo['tip'].hex())
  >     # create the notify file so caller knows we're running
  >     fpath = os.path.join('$d', 'notify')
  >     f = open(fpath, 'w')
  >     f.close()
  >     # wait for ack - caller should delete the notify file
  >     i = $maxwait
  >     while os.path.exists(fpath) and i > 0:
  >         time.sleep(1)
  >         i -= 1
  >     return True # reject the changesets
  > EOF

external hook

  $ cat <<EOF > reject.sh
  > printf 'hook '; hg tip --template '{node}\\n'
  > # create the notify file so caller knows we're running
  > fpath=$d/notify
  > touch \$fpath
  > # wait for ack - caller should delete the notify file
  > i=$maxwait
  > while [ -f \$fpath -a \$i != 0 ]; do
  >     sleep 1
  >     i=\`expr \$i - 1\`
  > done
  > exit 1 # reject the changesets
  > EOF

create repos

  $ hg init parent
  $ hg clone -q parent child-push
  $ hg clone -q parent child-pull
  $ echo a > child-push/a
  $ hg -R child-push add child-push/a
  $ hg -R child-push commit -m a -d '1000000 0'

test python hook

  $ cat <<EOF > parent/.hg/hgrc
  > [extensions]
  > reject = $d/reject.py
  > [hooks]
  > pretxnchangegroup = python:reject.rejecthook
  > EOF

  $ dotest
  push 29b62aeb769fdf78d8d9c5f28b017f76d7ef824b
  hook 29b62aeb769fdf78d8d9c5f28b017f76d7ef824b
  transaction abort!
  rollback completed
  abort: pretxnchangegroup hook failed
  pull 0000000000000000000000000000000000000000

test external hook

  $ cat <<EOF > parent/.hg/hgrc
  > [hooks]
  > pretxnchangegroup = sh $d/reject.sh
  > EOF

  $ dotest
  push 29b62aeb769fdf78d8d9c5f28b017f76d7ef824b
  hook 29b62aeb769fdf78d8d9c5f28b017f76d7ef824b
  transaction abort!
  rollback completed
  abort: pretxnchangegroup hook exited with status 1
  pull 0000000000000000000000000000000000000000