def test_appending_tree():
section = ExperimentSection(make_tree(['session', 'block', 'trial'], {}), ChainMap())
assert section.local_levels == {'block'}
section.append_design_tree(make_tree(['block-test', 'trial-test'], {'foo': 'bar'}), to_start=True)
assert section.local_levels == {'block', 'block-test'}
assert len(section) == 10
assert len(section[1]) == 4
assert len(section[5]) == 6
assert section[1].level == 'block-test'
assert section[1][1].level == 'trial-test'
assert section[1].data['foo'] == 'bar'
assert section[1][1].data['foo'] == 'bar'
assert section[1][1].data['trial-test'] == 1
assert section[5].data['block'] == 1
section.append_design_tree(make_tree(['block', 'trial'], {'foo': 'bar'}), to_start=True)
assert section[9].data['block'] == 5
with pytest.raises(ValueError):
section.append_design_tree(make_tree(['session', 'block', 'trial'], {}), ChainMap())
