anchor.diff:      a = datetime(1969, 12, 31, 23, 0, 0)
       tests(n) = assert(a % secondsSinceEpoch() == -3600, &
                         'datetime % secondsSinceEpoch(),  -1 hour')
  +    n = n + 1
  +
  +    a = datetime(2070, 1, 1)
  +    tests(n) = assert(a % secondsSinceEpoch() == 3155760000_int64, &
  +                      'datetime % secondsSinceEpoch(), 100 years')
       n = n + 1
   
       print '(71("-"))'
  
positive.code: module datetime_tests
    use datetime_module
    use, intrinsic :: iso_fortran_env, only: real64
  
    implicit none
  
  
negative.code:     print *
  
      ! Test counter; modify if adding new tests
      ntests = 192
  
      call initialize_tests(tests, ntests)
  
  