Telling svn from mercurial repository automatically is not always possible, or
at least not seamlessly. Let 'http://repo.com/svn' be an svn repository,
protected with basic authentication. Trying to clone it directly does something
like:
1- Open it like a mercurial repository:
* send between command, ask for credentials, fail
* fallback to static-http, ask for crendentials two times, fail
2- Open it like an svn repository
Mercurial [auth] facility is helpful here, but few people know about it, and it
may seem weird to store svn credentials in mercurial configuration. An svn-like
password manager would not help either because all connections attempts in [1]
fail and it's unlikely we would store credentials in this situation. Instead,
we can clone 'svn+http://repo.com/svn', which will skip step [1].
Since the ssh+svn URLs depend on supplied credentials, and because we want to
get the actual SVN URL without talking to the remote repository, we duplicate
the work done by SubversionRepo.
svn+ssh URLs are special because the authentication layer is not handled by
svn, so they must contain the username to be resolved seamlessly. Until now,
credentials supplied from the command line were ignored when rewriting those
URLs. Fix that.