Everything above the first '---' line (three dashes) is not a testcase. Lines of the form a=b ae checked for special name=value lines, such as tagset=NAME which sets the tagset or sentence=NAME which load a sentence.
After the --- line comes the first test -- the operator string, followed by an empty line, followed by the expected string output. The operator string can be multiline.
If the first operator line is "position=XXX", position is parsed as an int and that is used as the current position in the sentence for this and any following tests. Default position is 0.
Tests are separated from one another by a --- line.
This test loads no sentence, but can change the position anyway. Tagset is kipi by default.
