transcendental-lisp/lisp/compound-interest-test.lisp

(load "unit-test.lisp")
(load "compound-interest.lisp")

(unit
  (list

    (defun many-years-with-no-interest-rate ()
      (assert= 100000 (compound-interest 100000 0 10))
    )

    (defun no-years-with-positive-interest-rate ()
      (assert= 100000 (compound-interest 100000 10 0))
    )

    (defun one-year-with-positive-interest-rate ()
      (assert= 105000 (compound-interest 100000 5 1))
    )

    (defun two-years-with-positive-interest-rate ()
      (assert= 110250 (compound-interest 100000 5 2))
    )

    (defun three-years-with-positive-interest-rate ()
      (assert= 115763 (compound-interest 100000 5 3))
    )

    (defun four-years-with-positive-interest-rate ()
      (assert= 121551 (compound-interest 100000 5 4))
    )

    (defun one-year-with-negative-interest-rate ()
      (assert= 95000 (compound-interest 100000 -5 1))
    )

    (defun two-years-with-negative-interest-rate ()
      (assert= 90250 (compound-interest 100000 -5 2))
    )

    (defun three-years-with-negative-interest-rate ()
      (assert= 85737 (compound-interest 100000 -5 3))
    )

    (defun four-years-with-negative-interest-rate ()
      (assert= 81450 (compound-interest 100000 -5 4))
    )

    (defun negative-number-of-years ()
      (assert= 100000 (compound-interest 100000 5 -4))
    )

  )
)