Path coverage in Testing Fundamentals - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a path coverage test function.

Testing Fundamentals

def test_path_coverage():
    paths = [1]
    assert len(paths) > 0

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

A["path1", "path2"]

BNone

C[]

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using an empty list which means no paths to cover.

Using None which is not iterable.

The list ["path1", "path2"] represents multiple paths to cover, which is needed for path coverage testing.

2fill in blank

medium

Complete the code to check if all paths are covered.

Testing Fundamentals

def all_paths_covered(tested_paths, total_paths):
    return tested_paths [1] total_paths

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

A>

B==

C<

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' or '<' which do not guarantee full coverage.

Using '!=' which checks inequality.

For full path coverage, the number of tested paths must equal the total paths.

3fill in blank

hard

Fix the error in the path coverage assertion.

Testing Fundamentals

def test_paths():
    paths = ["p1", "p2", "p3"]
    covered = ["p1", "p3"]
    assert set(covered) [1] set(paths)

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

A<=

B<

C==

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' which requires exact match.

Using '>' or '<' which are incorrect for subset checks.

The covered paths should be a subset (or equal) of all paths, so '<=' is correct.

4fill in blank

hard

Fill both blanks to create a dictionary of path coverage status.

Testing Fundamentals

coverage_status = {path: (path [1] covered_paths) [2] True for path in all_paths}

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

Ain

Bnot in

C==

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'not in' which reverses the logic.

Using '==' which does not assign correct boolean.

We check if each path is in covered_paths and assign True or False accordingly using '!=' for comparison.

5fill in blank

hard

Fill all three blanks to filter paths with coverage and count them.

Testing Fundamentals

covered_count = len([path for path in all_paths if path [1] covered_paths and len(path) [2] [3]])

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

Ain

B>

C0

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'not in' which excludes covered paths.

Using '==' instead of '>' for length check.

We check if path is in covered_paths and if its length is greater than 0 to count valid covered paths.

Practice

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

easy

A. All possible routes through the code are tested

B. Only the most common routes are tested

C. Only the start and end points are tested

D. Only the user interface is tested

Solution

1. Step 1: Understand path coverage meaning

   Path coverage means testing every possible route or path through the code's decision points.

2. Step 2: Compare options with definition

   All possible routes through the code are tested matches this definition exactly, while others limit testing scope incorrectly.

3. Final Answer:

   All possible routes through the code are tested -> Option A

4. Quick Check:

   Path coverage = all routes tested [OK]

Hint: Path coverage means testing every route through code [OK]

Common Mistakes:

• Confusing path coverage with statement coverage
• Thinking it tests only common or simple paths
• Assuming it tests only UI or start/end points

2. Which of the following is the correct way to represent path coverage in a decision structure?

easy

A. Testing only the true branch of an if statement

B. Testing only the false branch of an if statement

C. Testing both true and false branches of an if statement

D. Skipping the if statement entirely

Solution

1. Step 1: Understand path coverage in decisions

   Path coverage requires testing all possible outcomes of decisions, including both true and false branches.

2. Step 2: Match options to requirement

   Only Testing both true and false branches of an if statement tests both branches, fulfilling path coverage requirements.

3. Final Answer:

   Testing both true and false branches of an if statement -> Option C

4. Quick Check:

   Both branches tested = path coverage [OK]

Hint: Test all branches of decisions for path coverage [OK]

Common Mistakes:

• Testing only one branch of a decision
• Ignoring false branches
• Skipping decision points

3. Consider this code snippet:

if (x > 0) {
  if (x < 10) {
    print("A");
  } else {
    print("B");
  }
} else {
  print("C");
}

How many unique paths must be tested for full path coverage?

medium

A. 2

B. 3

C. 4

D. 5

Solution

1. Step 1: Identify decision points and paths

   There are two if statements: outer (x > 0) and inner (x < 10). Paths are:
   1) x > 0 and x < 10 -> print "A"
   2) x > 0 and x >= 10 -> print "B"
   3) x <= 0 -> print "C"

2. Step 2: Count unique paths

   There are 3 unique paths through the code based on these conditions.

3. Final Answer:

   3 -> Option B

4. Quick Check:

   Two decisions create 3 paths [OK]

Hint: Count all decision outcomes to find paths [OK]

Common Mistakes:

• Counting only outer if branches
• Assuming paths multiply incorrectly
• Forgetting else branch path

4. You have this code:

if (a > 5) {
  if (b == 0) {
    print("X");
  }
} else {
  print("Y");
}

Which test case is missing for full path coverage?

medium

A. a = 6, b = 1

B. a = 6, b = 0

C. a = 4, b = 0

D. a = 4, b = 1

Solution

1. Step 1: Identify all paths

   Paths are:
   1) a > 5 and b == 0 -> print "X"
   2) a > 5 and b != 0 -> no print
   3) a <= 5 -> print "Y"

2. Step 2: Check test cases for coverage

   The test case a = 6, b = 1 covers path 2, which is missing from the others.

3. Final Answer:

   a = 6, b = 1 -> Option A

4. Quick Check:

   Test all branches including no-action paths [OK]

Hint: Include tests for conditions with no output too [OK]

Common Mistakes:

• Ignoring paths with no print or action
• Testing only true branches
• Missing else branch tests

5. Given this nested decision code:

if (x > 0) {
  if (y > 0) {
    print("P");
  } else {
    print("Q");
  }
} else {
  if (y > 0) {
    print("R");
  } else {
    print("S");
  }
}

How many test cases are needed for full path coverage, and why?

hard

A. 2, because only outer if matters

B. 5, because of extra hidden paths

C. 3, because some inner paths overlap

D. 4, because each if-else pair creates 2 paths

Solution

1. Step 1: Analyze nested if-else structure

   There are two if-else blocks nested:
   - Outer if (x > 0) with two inner paths (y > 0 and y <= 0)
   - Outer else (x <= 0) with two inner paths (y > 0 and y <= 0)

2. Step 2: Calculate total paths

   Each outer branch has 2 inner branches, so total paths = 2 (outer) * 2 (inner) = 4.

3. Final Answer:

   4, because each if-else pair creates 2 paths -> Option D

4. Quick Check:

   Nested if-else multiply paths = 4 [OK]

Hint: Multiply branches of nested decisions for paths count [OK]

Common Mistakes:

• Counting only outer or inner branches
• Assuming overlapping paths reduce count
• Adding extra paths without basis