PrimeFactor

1

	@Test
	public void factors() {
		assertThat(primeFactorsOf(1), is(Collections.emptyList()));
	}

null transfromation
null to constant transfromation

2

constant to variable: ArrayList<Integer> factors = new ArrayList<>()
split flow: if(n == 2)
refactor to more general(if n > 1)

3

constant to variable: factors.add(2) --> factors.add(n)

4

split flow: if n % 2 == 0
split flow: if n > 1
refactor: move if to outer
refactor: remove dup. in test. is(Arrays.asList(2, 2)) --> isListOf(2, 2)

5, 6, 7

8

if to while
- while은 단지 if의 일반화된 형식이고, if는 단지 while의 특별한 형식
refactor: while to for

9

make it pass by dup.
- 이 중복은 transform이 아님. 어느 것도 일반화하지 않았음.
일반화된 루프를 적용하여 중복을 제거
divisor 추출
refactor: while to for