portability fixes for some tests
Apparently the ls on OS X 10.3.9 exits with success even if the file
given on the command line doesn't exist
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
adding b
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
adding b