obsolete: explicitly track folds inside the markers
We now record information to be able to recognize "fold" event from
obsolescence markers. To do so, we track the following pieces of information:
a) a fold ID. Unique to that fold (per successor),
b) the number of predecessors,
c) the index of the predecessor in that fold.
We will now be able to create an algorithm able to find "predecessorssets".
We now store this data in the generic "metadata" field of the markers.
Updating the format to have a more compact storage for this would be useful.
This way of tracking a fold through multiple markers could be applied to split
too. This would have two advantages:
1) We get a simpler format, since number of successors is limited to [0-1].
2) We can better deal with situations where only some of the split successors
are pushed to a remote repository.
We should look into the relevance of such a change before updating the on-disk
format.
note: unlike splits, folds do not have to deal with cases where only some of
the markers have been synchronized. As they all share the same successor
changesets, they are all relevant to the same nodes.
#require hardlink
$ echo "[extensions]" >> $HGRCPATH
$ echo "relink=" >> $HGRCPATH
$ fix_path() {
> tr '\\' /
> }
$ cat > arelinked.py <<EOF
> from __future__ import absolute_import, print_function
> import os
> import sys
> from mercurial import util
> path1, path2 = sys.argv[1:3]
> if util.samefile(path1, path2):
> print('%s == %s' % (path1, path2))
> else:
> print('%s != %s' % (path1, path2))
> EOF
create source repository
$ hg init repo
$ cd repo
$ echo a > a
$ echo b > b
$ hg ci -Am addfile
adding a
adding b
$ cat "$TESTDIR/binfile.bin" >> a
$ cat "$TESTDIR/binfile.bin" >> b
$ hg ci -Am changefiles
make another commit to create files larger than 1 KB to test
formatting of final byte count
$ cat "$TESTDIR/binfile.bin" >> a
$ cat "$TESTDIR/binfile.bin" >> b
$ hg ci -m anotherchange
don't sit forever trying to double-lock the source repo
$ hg relink .
relinking $TESTTMP/repo/.hg/store to $TESTTMP/repo/.hg/store
there is nothing to relink
Test files are read in binary mode
$ "$PYTHON" -c "open('.hg/store/data/dummy.i', 'wb').write(b'a\r\nb\n')"
$ cd ..
clone and pull to break links
$ hg clone --pull -r0 repo clone
adding changesets
adding manifests
adding file changes
added 1 changesets with 2 changes to 2 files
new changesets 008c0c271c47
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd clone
$ hg pull -q
$ echo b >> b
$ hg ci -m changeb
created new head
$ "$PYTHON" -c "open('.hg/store/data/dummy.i', 'wb').write(b'a\nb\r\n')"
relink
#if no-reposimplestore
$ hg relink --debug --config progress.debug=true | fix_path
relinking $TESTTMP/repo/.hg/store to $TESTTMP/clone/.hg/store
tip has 2 files, estimated total number of files: 3
collecting: 00changelog.i 1/3 files (33.33%)
collecting: 00manifest.i 2/3 files (66.67%)
collecting: a.i 3/3 files (100.00%)
collecting: b.i 4/3 files (133.33%)
collecting: dummy.i 5/3 files (166.67%)
collected 5 candidate storage files
not linkable: 00changelog.i
not linkable: 00manifest.i
pruning: data/a.i 3/5 files (60.00%)
not linkable: data/b.i
pruning: data/dummy.i 5/5 files (100.00%)
pruned down to 2 probably relinkable files
relinking: data/a.i 1/2 files (50.00%)
not linkable: data/dummy.i
relinked 1 files (1.36 KB reclaimed)
$ cd ..
check hardlinks
$ "$PYTHON" arelinked.py repo/.hg/store/data/a.i clone/.hg/store/data/a.i
repo/.hg/store/data/a.i == clone/.hg/store/data/a.i
$ "$PYTHON" arelinked.py repo/.hg/store/data/b.i clone/.hg/store/data/b.i
repo/.hg/store/data/b.i != clone/.hg/store/data/b.i
#endif