If it ever issues a POST request, then it's HTTPv2. (In 1.7 HTTPv2 uses POSTs for commit, only.)
There are other ways to tell (without needing to commit), but I don't know them off the top of my head. Maybe notes/http-and-webdav/ (in trunk) has the information? Q. Chap wrote on Mon, Sep 24, 2012 at 20:39:50 +0200: > Hello, > > I've recently upgraded my svn client to 1.7. I'm not sure which version the > server is. It's not reported in the http headers. > > I guess it does not matter what the exact server version is, but how can I > verify if my client and the server are communicating via HTTPv2 or the older > http based protocol? > > Thank you