fit: check for negative numbers

Author: abdullyahuza

Recursive/Factorial.js

@@ -17,6 +17,10 @@ const factorial = (n) => {
  throw new RangeError('Not a Whole Number')
  }
 
+ if (n < 0) {
+ return undefined
+ }
+
  if (n === 0) {
  return 1
  }

Recursive/test/Factorial.test.js

@@ -15,4 +15,9 @@ describe('Factorial', () => {
  expect(() => factorial(undefined)).toThrow('Not a Number')
  expect(() => factorial(3.142)).toThrow('Not a Whole Number')
  })
+
+ it('Should return undefined for value less than 0', () => {
+ expect(factorial(-1)).toBe(undefined)
+ expect(factorial(-100)).toBe(undefined)
+ })
 })