Nope, you can't specify a global constant this way.
"parser.item.additionalItem.test" must be valid regular expression, which must
be used in "parser.lineRegExp", and then match the log lines. A guess if every
log line contains "Test" this holds true.
I can only see one use case for this: Several configurations (job-types) can use
the same row template file and "mark" the result with a constant. The solution
is to create one row template per configuration and include the constant in
hard-coded text.
Perhaps you had a different use case in mind that I missed?
Sorry for the late reply, have been away on vacation.
Best regards,
/Tor