Quiz 2 sample problems

In class Oct 8

• Study key terms from slides and labs.

• Study Knowledge Checks from labs.

• Emphasis on:

  • testing
    • I will not ask you to calculate coverage by hand.
  • control flow graphs (CFGs)
  • coding conventions and code documentation.
    • I do not expect you to memorize PEP8 rules or docstring formats.

• Repeat questions from previous quiz are on the table. No CLI.

• You may use your own written notes during the quiz.

• Multiple choice, fill-in-the-blank, long answer.

Sample CFG and Testing problems

You will be asked to draw CFGs and write test cases that cover all program paths.

Disclaimer: You will have other knowledge check questions beyond these types of questions.

Sample 1

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def is_prime(number):
    if number < 2:
        return False
    for i in range(2, int(number ** 0.5) + 1):
        if number % i == 0:
            return False
    return True

1. Draw the CFG for this code using the conventions from class.
2. List the unique program paths.
3. Add assert statements to the following test case that exercise all unique program paths.

   def test_is_prime():
      # Your code here.
   

Solution

CFG for is_prime()

def test_is_prime():
   # Some paths can be exercised with multiple input values. 
   # The goal is to exercise all program paths.

   assert is_prime(1) == True  # tests path (1, 2, 3)
   assert is_prime(2) == True  # path (1, 2, 4, 7)
   assert is_prime(4) == False  # path (1, 2, 4, 5, 6)
   assert is_prime(5) == True  # path (1, 2, 4, 5, 4, 7)

Sample 2

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def generate_fibonacci(n):
    if n <= 0:
        return "Error: Number of terms must be a positive integer"
    
    fibonacci_sequence = [1]
    a = 1
    b = 2
    count = 1
    
    while count < n:
        fibonacci_sequence.append(a)
        # Update values of a and b to the next numbers in the sequence
        a, b = b, a + b
        count += 1

    return fibonacci_sequence

1. Draw the CFG for this code using the conventions from class.
2. List the unique program paths.
3. Add assert statements to the following test case that exercise all unique program paths.

   def test_generate_fibonacci():
      # Your code here.
   

Solution

CFG for generate_fibonacci()

def test_generate_fibonnaci():
   # Some paths can be exercised with multiple input values. 
   # The goal is to exercise all program paths.

   assert generate_fibonnaci(0) == "Error: Number of terms must be a positive integer"  # tests path (14, 15, 16)
   assert generate_fibonnaci(1) == [1]  # path (14, 15, 18-21, 23, 29)
   assert generate_fibonnaci(6) == [1, 1, 2, 3, 5, 8]  # path (14, 15, 18-21, 23, 24-27, 23, 29)

Sample 3

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def factorial(n):
    # Input validation
    if not isinstance(n, int) or n < 0:
        return "Error: Input must be a non-negative integer"
    
    # Use iterative approach
    result = 1
    for i in range(1, n + 1):
        result *= i
    return result

1. Draw the CFG for this code using the conventions from class.
2. List the unique program paths.
3. Add assert statements to the following test case that exercise all unique program paths.

   def test_factorial():
      # Your code here.
   

Solution

CFG for factorial()

def test_factorial():
   # Some paths can be exercised with multiple input values. 
   # The goal is to exercise all program paths.

   assert factorial("Alice") == "Error: Number of terms must be a positive integer"  # tests path(36, 38, 39)
   assert factorial(-1) == "Error: Number of terms must be a positive integer"  # also tests path(36, 38, 39)
   assert factorial(0) == 1  # tests path(36, 38, 42, 43, 45)
   assert factorial(5) == 120  # tests path(36, 38, 42, 43, 44, 43, 45)