def rev_status_fast(git_session, rev)
    mod_dirs = module_dirs(git_session, rev)
    mod_stats = []
    git_session.within_exported_rev(rev, mod_dirs.collect{|d| "#{d}/#{RimInfo::InfoFileName}"}) do |temp_dir|
      mod_dirs.each do |rel_path|
        mod_stats << RevStatus::ModuleStatus.new(
          rel_path,
          RimInfo.from_dir("#{temp_dir}/#{rel_path}"),
          # never dirty
          false
        )
      end
    end
    stat = RevStatus.new(mod_stats)
    stat.git_rev = git_session.rev_sha1(rev)
    stat
  end
def rev_status_fast(git_session, rev)
    mod_dirs = module_dirs(git_session, rev)
    mod_stats = []
    git_session.within_exported_rev(rev, mod_dirs.collect{|d| "#{d}/#{RimInfo::InfoFileName}"}) do |temp_dir|
      mod_dirs.each do |rel_path|
        mod_stats << RevStatus::ModuleStatus.new(
          rel_path,
          RimInfo.from_dir("#{temp_dir}/#{rel_path}"),
          # never dirty
          false
        )
      end
    end
    stat = RevStatus.new(mod_stats)
    stat.git_rev = git_session.rev_sha1(rev)
    stat
  end
creates a RevStatus object for +rev+ with all modules assumend to be clean