def test_cannot_operate_on_rootless():
"""
Verify that operations do not work on a TreeBuilder when no root is created.
"""
builder = TreeBuilder()
with pytest.raises(ValueError):
builder.move_to_root()
with pytest.raises(ValueError):
builder.move_to_parent()
with pytest.raises(ValueError):
builder.build()
def test_after_creation_copy():
"""
Test that a single TreeBuilder can be used multiple times properly.
"""
builder = TreeBuilder()
builder.create_root(0)
builder.add_child(2, move=True)
builder.add_child(13)
builder.move_to_parent()
builder.add_child(7)
t1 = builder.build()
builder.move_to_root()
builder.set_data(4)
builder.add_child(3, move=True)
builder.add_child(15)
t2 = builder.build()
assert t2 is not t1
assert t2[0] is not t1[0]
assert t2[0][0] is not t1[0][0]
assert t2[1] is not t1[1]
assert t2.data == 4
assert t2[0].data == 2
assert t2[0][0].data == 13
assert t2[1].data == 7
assert t2[2].data == 3
assert t2[2][0].data == 15
assert len(t2) == 3
assert len(t2[0]) == 1
assert len(t2[1]) == 0
assert len(t2[2]) == 1