phases: sparsify phaseroots and phasesets
As final step of dealing with the holes in the phase numbers, make
phaseroots and phasesets both dictionaries indexed by the phase number.
Further adjust the interface of the C module by pushing the node to
revision mapping down as it is cheaper on the C side to deal with
revision numbers.
Overall, the patch series improves a no-change "hg up" for my NetBSD test
repository from 4.7s to 1.3s.
Differential Revision: https://phab.mercurial-scm.org/D8698
#require bzr
$ . "$TESTDIR/bzr-definitions"
$ cat > ghostcreator.py <<EOF
> import sys
> from bzrlib import workingtree
> wt = workingtree.WorkingTree.open('.')
>
> message, ghostrev = sys.argv[1:]
> wt.set_parent_ids(wt.get_parent_ids() + [ghostrev])
> wt.commit(message)
> EOF
ghost revisions
$ mkdir test-ghost-revisions
$ cd test-ghost-revisions
$ bzr init -q source
$ cd source
$ echo content > somefile
$ bzr add -q somefile
$ bzr commit -q -m 'Initial layout setup'
$ echo morecontent >> somefile
$ "$PYTHON" ../../ghostcreator.py 'Commit with ghost revision' ghostrev
$ cd ..
$ hg convert source source-hg
initializing destination source-hg repository
scanning source...
sorting...
converting...
1 Initial layout setup
0 Commit with ghost revision
$ glog -R source-hg
o 1@source "Commit with ghost revision" files+: [], files-: [], files: [somefile]
|
o 0@source "Initial layout setup" files+: [somefile], files-: [], files: []
$ cd ..