tests/test-bad-pull.out

performance: do not stat() things when not required

Ignore unknown files if we don't need them (eg in hg diff).
It slows things down a little bit for big trees (kernel repo), since _join()
is called for each file instead of for each directory.

fix issue567

abort: error: Connection refused
255
copy: No such file or directory
abort: HTTP Error 404
0