倒計時功能測試蟒蛇工作

Question

def test_countdown(self): 
    from_3 = '3\n2\n1\nBlastoff!' 
    self.assertEqual(countdown(3), from_3) 
    from_0 = 'Blastoff!' 
    self.assertEqual(countdown(0), from_0) 
#THIS IS THE TEST 
def countdown(n): 
    while n>0: 
     print(n) 
     n=n-1 
    print("Blastoff!") 
#This is my code for the function 

它不是通過測試，因爲它是走出來的「無」>倒計時後端（3）而不是「3 \ N2 \ N1 \ nBlastoff！」

Answer 1

你打印，不串聯：

def countdown(n): 
    return '\n'.join(map(str, range(n, 0, -1))) + '\nBlastoff!' 

或者像Lalaland以下建議：

def countdown(n): 
    result = '' 

    while n > 0: 
     result += str(n) + '\n' 
     n = n - 1 # decrement 

    result = result + '\nBlastoff!' 
    return result # not printing