Branch coverage in Testing Fundamentals - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to illustrate the branches in an if-else statement for branch coverage.

Testing Fundamentals

if condition:
    execute_true_branch()
else:
    execute_[1]_branch()

Drag options to blanks, or click blank then click option'

Afalse

Btrue

Cpath

Ddecision

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to test the else branch

Assuming only the true branch matters

The else branch must be executed to cover all branches.

2fill in blank

medium

Complete the code to ensure branch coverage for a function with two conditions.

Testing Fundamentals

def check_values(a, b):
    if a > 0:
        return 'Positive'
    elif b [1] 0:
        return 'Non-positive b'
    else:
        return 'Other'

Drag options to blanks, or click blank then click option'

A>=

B!=

C<=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' which only checks for zero

Using '!=' which excludes zero

The elif branch covers cases where b is less than or equal to zero.

3fill in blank

hard

Fix the error in the branch coverage test condition.

Testing Fundamentals

if score [1] 50:
    print('Pass')
else:
    print('Fail')

Drag options to blanks, or click blank then click option'

A<

B>=

C=>

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=>' which is a syntax error

Using '==' which only checks equality

The correct operator to check if score is at least 50 is '>='.

4fill in blank

hard

Fill both blanks to create a branch coverage test for a nested condition.

Testing Fundamentals

if temperature [1] 0:
    if weather [2] 'snowy':
        action = 'Stay inside'
    else:
        action = 'Go outside'

Drag options to blanks, or click blank then click option'

A>

B==

C!=

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' instead of '<' for temperature

Using '!=' instead of '==' for weather

The outer if checks if temperature is less than 0, and the inner if checks if weather equals 'snowy'.

5fill in blank

hard

Fill all three blanks to complete a branch coverage test with a dictionary comprehension.

Testing Fundamentals

results = {test[1]: outcome for test, outcome in tests.items() if outcome [2] 'fail' and 'critical' [3] test}

Drag options to blanks, or click blank then click option'

A.upper()

B==

Cin

D.lower()

Attempts:

3 left

💡 Hint

Common Mistakes

Using .upper() instead of .lower()

Using '!=' instead of '==' for outcome

Using '==' instead of 'in' for test name check

We convert test names to lowercase, check if outcome equals 'fail', and check if 'critical' is in the test name.

Practice

1. What does branch coverage testing ensure in software testing?

easy

A. All possible paths of each decision point are tested

B. Only the main function is tested

C. All variables are initialized

D. The software runs faster

Solution

1. Step 1: Understand branch coverage concept

   Branch coverage means testing every decision point in the code, including both true and false outcomes.

2. Step 2: Match concept to options

   All possible paths of each decision point are tested correctly states that all possible paths of each decision point are tested, which is the essence of branch coverage.

3. Final Answer:

   All possible paths of each decision point are tested -> Option A

4. Quick Check:

   Branch coverage = all decision paths tested [OK]

Hint: Branch coverage tests both true and false paths [OK]

Common Mistakes:

• Confusing branch coverage with statement coverage
• Thinking it only tests main functions
• Assuming it improves speed

2. Which of the following is the correct way to write a branch coverage test condition in pseudocode?

easy

A. print('Test complete')

B. while x > 10 do A

C. for i in range(10): do A

D. if (x > 10) then do A else do B

Solution

1. Step 1: Identify branch decision structure

   Branch coverage requires a decision point with two or more paths, like an if-else condition.

2. Step 2: Check options for decision points

   if (x > 10) then do A else do B shows an if-else statement, which has two branches (true and false). Other options do not have decision branches.

3. Final Answer:

   if (x > 10) then do A else do B -> Option D

4. Quick Check:

   If-else = branch decision [OK]

Hint: Look for if-else to identify branches [OK]

Common Mistakes:

• Choosing loops as branch examples
• Ignoring else part of if-else
• Confusing print statements with branches

3. Consider the following code snippet:

if (a > 0) {
  if (b == 5) {
    print('Path 1');
  } else {
    print('Path 2');
  }
} else {
  print('Path 3');
}

How many test cases are needed for 100% branch coverage?

medium

A. 3

B. 4

C. 2

D. 5

Solution

1. Step 1: Identify decision points and branches

   There are two if statements: outer (a > 0) with true/false branches, inner (b == 5) with true/false branches.

2. Step 2: Count unique branches

   Outer if: 2 branches (true, false). Inner if (only if outer true): 2 branches. Total branches = 3 unique paths: Path 1, Path 2, Path 3.

3. Final Answer:

   3 -> Option A

4. Quick Check:

   Branches = 3 paths [OK]

Hint: Count all true/false branches in nested ifs [OK]

Common Mistakes:

• Counting only outer if branches
• Assuming each if adds 2 test cases independently
• Ignoring nested structure

4. You have this code:

if (x != 0) {
  print('Non-zero');
}

A test case with x = 0 is missing. What branch coverage issue does this cause?

medium

A. True branch not tested

B. False branch not tested

C. Syntax error in code

D. All branches covered

Solution

1. Step 1: Identify branches in the if condition

   The if condition has two branches: true (x != 0) and false (x == 0).

2. Step 2: Analyze test cases given

   Only test cases with x != 0 exist, so true branch is tested but false branch (x == 0) is missing.

3. Final Answer:

   False branch not tested -> Option B

4. Quick Check:

   Missing false branch test = coverage gap [OK]

Hint: Test both true and false conditions for full coverage [OK]

Common Mistakes:

• Assuming one test case covers all branches
• Confusing true and false branches
• Thinking missing test causes syntax error

5. Given this code:

if (score >= 90) {
  grade = 'A';
} else if (score >= 75) {
  grade = 'B';
} else {
  grade = 'C';
}

How many test cases are needed for 100% branch coverage?

hard

A. 2

B. 5

C. 3

D. 4

Solution

1. Step 1: Identify all decision points and branches

   There are two if conditions: first (score >= 90) with true/false branches, second (score >= 75) with true/false branches inside else.

2. Step 2: Count unique branches

   Branches: first if true (score>=90), first false + second true (75<=score<90), first false + second false (score<75). Total 3 test cases needed for 100% coverage.

3. Final Answer:

   3 -> Option C

4. Quick Check:

   if-else-if-else chain = 3 test cases [OK]

Hint: Count all true/false branches in if-else if-else chains [OK]

Common Mistakes:

• Counting only if statements, ignoring else
• Assuming 4 test cases are needed
• Missing nested else if branches