1. Test Design Techniques Software Testing: IN3240 / IN4240

2. Summary Specification-based testing Structure-based testing
Equivalence partitioning [x]
Boundary value analysis [x]
Decision table
State transition
Use case testing
Structure-based testing
Statement coverage
Decision coverage

3. Decision Table How do you create a decision table?
What are the conditions?
Anything that can be evaluated using boolean values!
How many rules are there?
2 𝑁 where N = number of conditions
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Rule 1
Rule 2
Rule 3
Rule 4
Conditions X? T F Y?
Result
Do stuff
Do other stuff
Transfer things
Ignore

4. Decision Table (exercise)
An education program at a Norwegian university have the following admission requirements:
To obtain a study place, the applicant must have a general academic qualification, the mathematic course R1 from upper secondary school, and GPA above the limit of the year.
If the applicant’s GPA are below the limit, the individual is put into the waiting list, assuming that he/she have a general academic qualification and have taken R1.
If the applicant has a general qualification, but not taken the mathematics course, the applicant is offered a preparatory course in mathematics, assuming that the GPU are above the limit
Draw the decision table which shows all possible combinations
Simplify the decision table and reduce the number of rules while retaining the same functionality
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5. Decision Table (exercise)
Draw the decision table which shows all possible combinations
Simplify the decision table and reduce the number of rules while retaining the same functionality
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Conditions R1 R2 R3 R4 R5 R6 R7 R8
Gen. Ac. Qualification T F
Math. Course
GPA above
Actions
Enroll
Waiting list
Prep. Course
Ignore

6. Decision Table (exercise)
Draw the decision table which shows all possible combinations
Simplify the decision table and reduce the number of rules while retaining the same functionality
Assumption: Every combinations other than the ones presented will result in ignore / not enrolled
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Conditions R1 R2 R3
Gen. Ac. Qualification T
Math. Course F
GPA above
Actions
Enroll
Waiting list
Prep. Course

7. State transition testing
“A black box technique in which test cases are designed to execute valid and invalid state transitions”
Describes the aspects of the system
Finite
A finite number of states
State
A stable situation where the process awaits stimuli
State diagrams consist of four parts:
The states that the software/system may occupy
The transitions from one state to another
The events that cause a transitions
The actions that result from a transition
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8. State transition testing
“A black box technique in which test cases are designed to execute valid and invalid state transitions”
State diagrams consist of four parts:
The states that the software/system may occupy
The transitions from one state to another
The events that cause a transitions
The actions that result from a transition
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9. State transition testing (exercise)
A website shopping basket starts out empty. As purchases are selected, they are added to the shopping basket. Items can also be removed from the basket.
When the customer decides to check out, a summary of the items and the total cost are shown. Customer states if the information is ok
If the contents and the price are OK, then the customer will be redirected to the payment system. Otherwise, you go back to shopping
Produce a state diagram
Define a sequence to cover all transitions
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10. State transition testing (exercise)
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11. State table Maps out states and transitions in tabular form
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12. Exercise 2(b): Answer project title
State table also shows what’s not legal transitions from a state.
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13. Use Case testing
“Technique to help identify test cases that exercise the whole system from start to finish”
A description of a particular use of the system by an actor (user of the system)
Each use case describes the interaction between the actor and the system to achieve a specific task
A sequence of steps from start to finish
May uncover integration defects
Actors may not only be users, but also other systems!
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14. Use Case testing Step Description Main Success Scenario A: Actor
S: System 1
A: Inserts card 2
S: Validates card and asks for pin 3
A: Enters pin 4
S: Validates pin 5
S: Allows access to account
Extensions 2a
Card not valid
S: Display message and reject card 4a
Pin not valid
S: Display error, go back to step 3 4b
Pin invalid 3 times
S: Eat card and exit
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15. Use Case testing Step Description Main Success Scenario A: Actor
S: System 1
A: Inserts card 2
S: Validates card and asks for pin 3
A: Enters pin 4
S: Validates pin 5
S: Allows access to account
Extensions 2a
Card not valid
S: Display message and reject card 4a
Pin not valid
S: Display error, go back to step 3 4b
Pin invalid 3 times
S: Eat card and exit
For a vending machine, create a test case for normal usage
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16. Use Case testing
For a vending machine, create a test case for normal usage
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17. Summary Specification-based testing Structure-based testing
Equivalence partitioning [x]
Boundary value analysis [x]
Decision table [x]
State transition [x]
Use case testing [x]
Structure-based testing
Statement coverage
Decision coverage

18. Test Coverage Statement and Decision coverage
Questions regarding coverage is usually in conjunction with control flow diagrams
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19. Statement Coverage Example: Statement coverage Test 1_1: A = 2, B = 3
Which statements have we covered?
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20. Statement Coverage Example: Statement coverage
Have covered 5 out of 6 statements
Statement coverage = 83 %
Need another test to reach 100 %
Test 1_4:
A = 20, B = 25
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In fact, only one test case needed

21. Decision Coverage Decision coverage
One test required for 100 % statement coverage
A = 12, B = 10
// All statements are exercised
Decision coverage requires:
Each condition must have True and False
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22. Decision Coverage
Which of the following statements about the relationship between statement and decision coverage is correct?
Decision coverage
Additional test case
A = 2, B = 4
// All decisions have been exercised
Have achieved 100 % decision coverage
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23. Test Coverage (Exercise)
If you are flying with an economy ticket, there is a possibility that you may get upgraded to business class, especially if you hold a gold card in the airline’s frequent flyer program.
If you don’t hold a gold card, there is a possibility that you will get “bumped” off the flight if it is full and you check in late.
This is shown in the following figure. Note that each box (i.e. statement) has been numbered.
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24. Test Coverage (Exercise)
Tests run:
Test 1
Gold card holder who gets
upgraded to business class
Test 2
Non-gold card holder
who stays in economy
Test 3
A person who is
bumped off the flight
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25. Test Coverage (Exercise) on 7
What is the statement coverage of these three tests?
60 %
70 %
80 %
90 %
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26. Test Coverage (Exercise 2)
A vending machine dispenses either hot or cold drinks.
If you choose a hot drink (e.g. tea or coffee),
it asks if you want milk (added if required).
Then it asks if you want sugar (added if required)
Finally, the drink is dispensed.
Draw a control flow diagram for this example
Hint: Regard the selection
of the type of drink as one statement
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27. Test Coverage (Exercise 2)
Draw a control flow diagram for this example
7. Construct the control flow diagram combining all elements
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28. Test Coverage (Exercise 2)
Given the following tests, what is the statement coverage achieved? What is the decision coverage achieved?
Test 1: Cold drink
Test 2: Hot drink with milk and sugar
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29. Test Coverage (Exercise 2)
Statement and decision coverage
Test 1:
Cold drink
Test 2:
Hot drink with milk and sugar
What is the statement coverage?
What is the decision coverage?
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30. Test Coverage (Exercise 2)
Statement and decision coverage
Statement coverage
100 % statement coverage
Every statement has been covered
(All boxes have been touched)
What is the decision coverage?
How many decision outcomes exist?
How many decision outcomes exercised?
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31. Test Coverage (Exercise 2)
Statement and decision coverage
What is the decision coverage?
How many decision outcomes exist?
Hot / Cold / Yes / No / Yes / No
6 decision outcomes in total
How many decision outcomes exercised?
Hot / Cold / Yes / No
4 decision outcomes exercised
Decision coverage
4 / 6 = 67 %
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32. Test Coverage (Exercise 2)
What additional tests would be needed to achieve 100% decision and statement coverage?
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33. Test Coverage (Exercise 2)
What additional tests would be needed to achieve 100% decision and statement coverage?
Additional tests
Statement coverage:
No further tests
Decision coverage
Must exercise No / No
Test 3:
Hot drink, no milk, no sugar
All decisions exercised
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34. Summary Specification-based testing Structure-based testing
Equivalence partitioning [x]
Boundary value analysis [x]
Decision table [x]
State transition [x]
Use case testing [x]
Structure-based testing
Statement coverage [x]
Decision coverage [x]