While here, change how we check if the current line is the last one.
Before, we just checked if there were more files after the current one.
Now, we check the actual content of those files: they files may not have
a line at all. This matches the definition of the "last line" by the
Open Group.
The new behavior is closer to GNU sed.
PR: 160745
Phabric: https://phabric.freebsd.org/D431
Reviewed by: jilles
Approved by: jilles
Exp-run by: antoine
I'm starting with the easy cases. The leftovers need to be looked at a
bit more closely.
Note that this change _does_ modify the code of the old tests. This is
required in order to allow the code to locate the data files in the
source directory instead of the current directory, because Kyua
automatically changes the latter to a temporary directory.
Also note that at least one test is known to be broken here. Actually,
the test is not really broken: it's marked as a TODO but unfortunately
Kyua's TAP parser currently does not understand that. Will have to be
fixed separately.