Sum Property Based tested

class PropertyTestSum : StringSpec({
    "Sum is commutative " {
        assertAll { a: Int, b: Int ->
            sum(a, b) shouldBe sum(b, a)
        }
    }

    "Sum is associative " {
        assertAll { a: Int, b: Int, c: Int ->
            sum(a, b, c) shouldBe sum(a, c, b)
            sum(a, b, c) shouldBe sum(c, b, a)
            sum(a, b, c) shouldBe sum(b, c, a)
        }
    }

    "The sum of any number and zero is the original number" {
        assertAll { a: Int ->
            sum(a, 0) shouldBe a
        }
    }

    "Sum is distributive " {
        assertAll { a: Int, b: Int, c: Int ->
            sum(a, b) * c shouldBe sum(a * c, b * c)
        }
    }