Currently SVN fixture file at `arcanist/src/repository/api/__tests__/state/svn_basic.svn.tgz` path is in SVN 1.7 format. This makes it impossible to run unit tests if installed SVN version is 1.6.
I guess SVN version needs to be checked to call `svn upgrade` only when SVN is > 1.6, because there was no such command in SVN 1.6 or below.