convert/svn: delegate to svn bindings if HTTP probe fails
convert extension tries to guess the remote repository type with HTTP probes.
Unfortunately, it does not handle authentication or HTTPS handshakes, so regular
svn repositories may be excluded. Instead, when a non-404 error is retrieved,
we keep trying with the svn bindings. The drawback is missing svn bindings will
make the conversion to fail even for non-svn targets. This can be avoided with
--source.
% init foo-base
% create alpha in first repo
adding alpha
% clone foo-base to foo-work
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
% create beta in second repo
adding beta
% create gamma in first repo
adding gamma
% pull into work and merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
% revert to changeset 1 to simulate a failed merge
2 files updated, 0 files merged, 0 files removed, 0 files unresolved