branchcache: skip entries that are topological heads in the on disk file
In the majority of cases, topological heads are also branch heads. We have
efficient way to get the topological heads and efficient way to retrieve
their branch information. So there is little value in putting them in the branch
cache file explicitly. On the contrary, writing them explicitly tend to create
very large cache file that are inefficient to read and update.
So the branch cache v3 format is no longer including them. This changeset focus
on the format aspect and have no focus on the performance aspect. We will cover
that later.
#require no-windows
$ . "$TESTDIR/remotefilelog-library.sh"
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> server=True
> EOF
$ echo x > x
$ hg commit -qAm x
$ echo y >> x
$ hg commit -qAm y
$ echo z >> x
$ hg commit -qAm z
$ hg update 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo w >> x
$ hg commit -qAm w
$ cd ..
Shallow clone and activate getflogheads testing extension
$ hgcloneshallow ssh://user@dummy/master shallow --noupdate
streaming all changes
3 files to transfer, 908 bytes of data (no-rust !)
transferred 908 bytes in * seconds (*/sec) (glob) (no-rust !)
5 files to transfer, 1.01 KB of data (rust !)
transferred 1.01 KB in * seconds (* */sec) (glob) (rust !)
searching for changes
no changes found
$ cd shallow
$ cat >> .hg/hgrc <<EOF
> [extensions]
> getflogheads=$TESTDIR/remotefilelog-getflogheads.py
> EOF
Get heads of a remotefilelog
$ hg getflogheads x
2797809ca5e9c2f307d82b1345e832f655fb99a2
ca758b402ddc91e37e3113e1a97791b537e1b7bb
Get heads of a non-existing remotefilelog
$ hg getflogheads y
EMPTY