def transform(t):
ptb.remove_empty_elements(t)
ptb.simplify_labels(t)
return ptb.add_root(t, 'ROOT')
('PRP', 0, 1),
('ADVP', 1, 2),
('RB', 1, 2),
('VP', 2, 6),
('VBZ', 2, 3),
('NP-PRD', 3, 6),
('DT', 3, 4),
('NN', 4, 5),
('NN', 5, 6),
(',', 6, 7),
('NP-SBJ', 7, 8),
('NNS', 7, 8),
('VP', 8, 9),
('VBP', 8, 9),
('SBAR', 9, 9),
('S', 9, 9),
('-NONE-', 9, 9),
('-NONE-', 9, 9),
('.', 9, 10)
]
t = next(ptb.parse(tree))
u = next(ptb.parse(transformed_tree))
expectequal( set(spans) , set(ptb.all_spans(t)) )
ptb.remove_empty_elements(t)
ptb.simplify_labels(t)
t = ptb.add_root(t)
expectequal( set(ptb.all_spans(t)) , set(ptb.all_spans(u)) )