def test_list_recursion(list_env):
parse_expression(
"(define (sum lon) (if (empty? lon) 0 (+ (car lon) (sum (cdr lon)))))",
list_env,
).eval(list_env)
assert parse_expression("(sum 5to1)", list_env).eval(list_env) == Atom(15)
def test_expressions(self):
self.assertEqual(parse_expression("three plus four"), "3 + 4")
self.assertEqual(
parse("space greater than five and number of cars less than four"),
"space > 5 "
"and "
"number_of_cars "
"< 4")
self.assertEqual(
parse(
"three plus four is less than number of cars and x is greater than five"
), "3 + 4 < number_of_cars and x > 5")
self.assertEqual(parse("index or number of times"),
"index or number_of * ")
self.assertEqual(parse_expression("three mod four division two"),
"3 % 4 / 2")
self.assertEqual(
parse(
"space greater or equal to five and number of cars less or equal to four"
), "space >= 5 "
"and "
"number_of_cars "
"<= 4")
self.assertEqual(
parse(
"space greater or equal to one hundred and number of cars less or equal to four"
), "space >= 100 "
"and "
"number_of_cars "
"<= 4")
def test_higher_order(list_env):
parse_expression(
"(define (map f lox) (if (empty? lox) empty (cons (f (first lox)) (map f (rest lox)))))",
list_env,
).eval(list_env)
assert (str(
parse_expression("(map (lambda (n) (+ n 1)) 5to1)", list_env).eval(
list_env)) == "(cons 6 (cons 5 (cons 4 (cons 3 (cons 2 empty)))))")
def test_recursion(basic_env):
parse_expression("(define (fact n) (if (zero? n) 1 (* n (fact (- n 1)))))",
basic_env).eval(basic_env)
assert parse_expression("(fact 5)", basic_env).eval(basic_env) == Atom(120)
def test_define_function(basic_env):
parse_expression("(define (test a) (or true a))",
basic_env).eval(basic_env)
assert parse_expression("(test false)", basic_env).eval(basic_env) is true
def test_define_lambda(basic_env):
parse_expression("(define sqr (lambda (x) (* x x)))",
basic_env).eval(basic_env)
assert parse_expression("(sqr 2)", basic_env).eval(basic_env) == Atom(4)
def test_builtin_math(basic_env):
assert parse_expression("(+ 1 2)", basic_env).eval(basic_env) == Atom(3)
assert parse_expression("(* 3 4)", basic_env).eval(basic_env) == Atom(12)
assert parse_expression("(- 3 9)", basic_env).eval(basic_env) == Atom(-6)
assert parse_expression("(/ 15 5)", basic_env).eval(basic_env) == Atom(3)
def test_define_constant(basic_env):
parse_expression("(define TEST false)", basic_env).eval(basic_env)
assert parse_expression("TEST", basic_env).eval(basic_env) is false
def test_boolean_logic(basic_env):
assert (parse_expression(
"(if (and true true false) false (or false true))",
basic_env).eval(basic_env) is true)
def test_constant_eval(basic_env):
assert parse_expression("true", basic_env).eval(basic_env) is true
def list_env(basic_env):
parse_expression(
"(define 5to1 (cons 5 (cons 4 (cons 3 (cons 2 (cons 1 empty))))))",
basic_env,
).eval(basic_env)
return basic_env