def test_orthogonal_line_split_segment(self):
canvas = Canvas()
line = Line()
canvas.add(line)
assert len(canvas.solver._constraints) == 0
line.orthogonal = True
assert len(canvas.solver._constraints) == 2
after_ortho = set(canvas.solver._constraints)
assert len(line.handles()) == 3
del undo_list[:]
line.split_segment(0)
assert len(canvas.solver._constraints) == 3
assert len(line.handles()) == 4
undo()
assert len(canvas.solver._constraints) == 2
assert len(line.handles()) == 3
assert canvas.solver._constraints == after_ortho
line.split_segment(0)
assert len(canvas.solver._constraints) == 3
assert len(line.handles()) == 4
after_split = set(canvas.solver._constraints)
del undo_list[:]
line.merge_segment(0)
assert len(canvas.solver._constraints) == 2
assert len(line.handles()) == 3
undo()
assert len(canvas.solver._constraints) == 3
assert len(line.handles()) == 4
assert canvas.solver._constraints == after_split
