bundle: avoid crash when no good changegroup version found
When using treemanifests, only changegroup3 bundles can be
created. However, there is currently no way of requesting a
changegroup3 bundle, so we run into an assertion in
changegroup.getbundler() when trying to get a changroup2
bundler. Let's avoid the traceback and print a short error message
instead.
#require unix-permissions no-root
$ hg init a
$ cd a
$ echo foo > b
$ hg add b
$ hg ci -m "b"
$ chmod -w .hg/store
$ cd ..
$ hg clone a b
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ chmod +w a/.hg/store # let test clean up
$ cd b
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
$ cd ..