Fixed OSError "No such file or directory: None" and make IOError consistent.
The None error occurs when the current working directory is no longer
available, e.g. because it was removed in another shell.
adding foo
adding bomb
adding a.c
adding dir/a.o
adding dir/b.o
! a.c
! dir/a.o
! dir/b.o
? .hgignore
a.c: unsupported file type (type is fifo)
! a.c
# test absolute path through symlink outside repo
A f
# try symlink outside repo to file inside
abort: ../z not under root