topic: add tests to demonstrate topic confuses the branchhead checking logic
While topics are in play, we store the branchheads (which has a topic)
in "branchname:topicname" format. After digging into it I found that
even in the case when we should have branch heads for "bname:tname"
we get heads for "bname".
The tests output reflect the confusion in branch head checking logic.
Next patch will be fixing the problem.
Test that share-clones use the cache in the original repository.
$ . $TESTDIR/testlib/common.sh
$ hg init share-base
$ cd share-base/
$ cat >> .hg/hgrc <<EOF
> [extensions]
> evolve=
> share=
> EOF
$ hg debugbuilddag .+3:branchpoint+4*branchpoint+2
$ cd ..
$ hg --config extensions.share= share -U share-base share-client
$ cd share-client
$ hg debugupdatecache
$ test -d .hg/cache
[1]
$ test -d ../share-base/.hg/cache