from abjad import *


def test_listtools_negate_elements_at_indices_01( ):

   l = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
   t = listtools.negate_elements_at_indices(l, [0, 1, 2])
   
   assert t == [-1, -2, -3, 4, 5, 6, 7, 8, 9, 10]


def test_listtools_negate_elements_at_indices_02( ):

   l = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
   t = listtools.negate_elements_at_indices(l, [0, 1, 2], period = 5)
   
   assert t == [-1, -2, -3, 4, 5, -6, -7, -8, 9, 10]
