Rotate a list with test

rotate.py

class Solution(object):
  def rotate(self, nums, k):
    n = len(nums)
    if n == 0:
      return
    start = 0
    count = 0
    while count < n:
      curr = start
      tmp = nums[curr]
      while True:
        next = (curr + k) % n
        nextval = nums[next]
        nums[next] = tmp
        curr = next
        tmp = nextval
        count += 1
        if curr == start:
          break
      start += 1

rotate_test.py

import unittest
from rotate import Solution


class MyTestCase(unittest.TestCase):

  def setUp(self):
    self.s = Solution()

  def testNormalCase(self):
    nums = [1, 2]
    k = 1
    self.s.rotate(nums, k)
    expect_nums = [2, 1]
    self.assertEqual(nums, expect_nums)

  def testArrayLengthZero(self):
    nums = []
    k = 1
    self.s.rotate(nums, k)
    expect_nums = []
    self.assertEqual(nums, expect_nums)


if __name__ == '__main__':
    unittest.main()