The Parse Tree operator parses embedded lists. The type representing the embedded list implements the fitlibrary.tree.Tree interface.

when test is⇓ story test fixture check test result sample domain set tree field root check tree field root sample domain set tree field root check tree field root

sample domain set tree field root check tree field root

then result is

sample domain set tree field root check tree field root

when test is⇓ story test fixture check test result sample domain set tree field root branch leaf1 leaf2 twig check tree field root branch leaf1 leaf2 twig sample domain set tree field root branch leaf1 leaf2 twig check tree field root branch leaf1 leaf2 twig

sample domain set tree field root branch leaf1 leaf2 twig check tree field root branch leaf1 leaf2 twig

then result is

sample domain set tree field root branch leaf1 leaf2 twig check tree field root branch leaf1 leaf2 twig