stest’s hidden file pruning is implemented as a simple `name[0] != '.'`
check, which produces confusing behavior when examining paths with more
than one component. For example, users expect `foo` and `./foo` to refer
to the same file, but for stest, these are different:
/etc$ ls passwd
passwd
/etc$ echo passwd | stest -f
passwd
/etc$ echo ./passwd | stest -f
/etc$
Users would also likely be surprised by stest’s inclusion of hidden
files inside subdirectories:
$ mkdir foo
$ touch foo/.bar
$ echo foo/.bar | stest -f
foo/.bar
$