tests/library-infinitepush.sh

rust: speed up zstd decompression by re-using the decompression context

Admittedly, zstd is already pretty fast, but this change makes it
a bit faster yet: it saves ~5% of time it takes to read our large repo.

The actual motivating use case is treemanifest: in treemanifest
we end up reading *lots* of small directories, and many of them
need decompression, and there the saving for [rhg files] is >10%.
(which also seems unreasonable, we should probably keep things uncompressed more)

scratchnodes() {
  for node in `find ../repo/.hg/scratchbranches/index/nodemap/* | sort`; do
     echo ${node##*/} `cat $node`
  done
}

scratchbookmarks() {
  for bookmark in `find ../repo/.hg/scratchbranches/index/bookmarkmap/* -type f | sort`; do
     echo "${bookmark##*/bookmarkmap/} `cat $bookmark`"
  done
}

setupcommon() {
  cat >> $HGRCPATH << EOF
[extensions]
infinitepush=
[infinitepush]
branchpattern=re:scratch/.*
EOF
}

setupserver() {
cat >> .hg/hgrc << EOF
[infinitepush]
server=yes
indextype=disk
storetype=disk
reponame=babar
EOF
}