1) The document provides an overview of different test case design techniques including specification based testing, input domain testing, risk based testing, and scenario testing. 2) Specification based testing techniques discussed include analyzing specifications for gaps or contradictions, gathering additional information from developers, and using the 5W1H technique to derive test cases. 3) Input domain testing techniques like equivalence partitioning and boundary value analysis are covered to avoid redundant test cases around inputs. 4) Risk based testing involves imagining how a program could fail, assessing the likelihood and impact of failures, and designing test cases to expose potential failures. 5) Scenario testing uses real user personas and examples of how the software will be used to further

1. First Time QE - 2010
Test Case Design
Catalin Anastasoaie
V1.1 1

2. Photo by DaveBleasdale
Test Design – Agenda
• Why do we test?
• Test Case Design
– Specification based testing
– Input Domain testing
– Risk based testing
– Scenario testing
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3. Why do we test?
• “Testing is questioning a product in order to
evaluate it”, by James Bach
• “Software testing is an investigation
conducted to provide stakeholders with
information about the quality of the product.”,
by Wikipedia
3Photo by tj scenes

4. Test Case Design
• Specification based testing
• Input Domain testing
• Risk based testing
• Scenario testing
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5. Specification Based Testing
• Look for any specification
• Figure out what it says
– Analyze
– Gather more
information
• Write test cases
– 5W1H
– Decision Table
– State Transition
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6. Specification: Analyze
• What’s missing?
• Will it work?
• Will it make sense for the user?
• Can I test this?
• Can I measure them?
• How will I find out if it works?
• Are there any contradictions?
6Photo by gcbb

7. Specification: Gather more info
• Ask for clarifications
• Point to the Elephant in the room
• Talk to the developer(s)
– Ask them about the risky parts
– Is there anything that they might want to share with
you?
7Photo by Carolyn Coles

8. Specification: 5W1H
• Who?
• What?
• Where?
• When?
• Why?
• How?
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9. Specification: Write test cases
“The baby duck will swim in the pond each day.”
Who?
Is it a baby?
Will it grow old?
What does he eat?
What?
Can it swim?
For how long?
Where?
How big is the
pond?
How deep is it?
Salty or sweet?
When?
Each day?
Day and night?
What about
the weather?
Why?
• Will it always swim?
• Hungry?
• Need to go somewhere?
• Sightseeing?
• Following his mother?
How?
• How will it swim with broken leg?
• How will it submerge if the lake is
salty?
9Photo by on1stsite

10. Specification: Example
• Now let’s play with the calendar application
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11. Specification: Decision Table
• Useful in systems where combinations of input
conditions produce different actions
• A way to capture system requirements that
contain logical conditions
• Relation between cause and effect
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12. Decision Table Example
• A pizza delivery place has the following
discount rules:
– If you’re a regular customer, you get 5%
– For any order higher than 100 RON, customer gets
a 5% discount and if you order what’s on the
special offer for that day, an additional 2%
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13. Specification: Decision Table
Test Case 1 Test Case 2 Test Case 3
Condition 1 T F F
Condition 2 T T F
Condition 3 F T F
Action 1 Y N N
Action 2 N Y N
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14. Specification: State Transition
• Useful in systems characterized by a “finite
number of states”
– Behavior depends on current and past state(s)
• Create state transition diagrams
• Derive state tables
• Use the state tables to derive test cases
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15. State Transition
Test Case 1 2 3 4 5
Initial State S1 S1 S2 S2 S3
Action Sign Up Login Click Link Resend
validation
(Click) link
Login
Final State S2 S1 S3 S2 S4
Expected
Results
Created
Account,
Send
confirmatio
n link
Wrong
Credentials
Validated
Account
Resent
validation
link
Logged In
A login system works like this: in order to login, the user has to
first sign up to register a new account, and validate the account
using the validation link sent to the e-mail address that he
provides
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16. Input Domain Testing
• Equivalence Partitioning
• Boundary Testing
16Photo by fdecomite

17. Domain Testing: Equivalence
Partitioning
• To avoid unnecessary testing, partition
(divide) the range of inputs into groups of
equivalent tests.
• We treat two tests as equivalent if they are so
similar to each other that it seems pointless to
test both.
• Select an input value from the equivalence
class as representative of the full group.
17Photo by TheBusyBrain

18. Domain Testing: Boundary Analysis
• Behavior at the edge
of each equivalence
partition is more
likely to be incorrect
• Maximum and
minimum values of a
partition
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• Both valid and invalid boundary values
Photo by ground.zero

19. Domain: Examples
• Calculator (add two numbers) A + B = SUM
A B SUM
[-99 .. 99] [-99 .. 99] [-198 .. 198]
> 99 > 99 > 198
< -99 < -99 < -198
-100 … …
… 100 …
-101 … …
… 101 …
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20. Risk Based Testing
• Imagine how the program could fail
• Design test cases to expose these (potential)
failures
20Photo by kyz

21. Risk Based Testing
• A way the program could fail
• How likely it is that the program could fail in
that way
• What the consequences of that failure could
be
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22. Risk Based Testing - Example
Failure Probability Consequence
The lake will freeze High The duck will not be able
to swim nor to eat
The duck will break one leg Low Swim in circles?
The pond will dry out Medium Not being able to swim
“The baby duck will swim in the pond each day.”
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23. Risk Based Testing: Example
• Now let’s do some risk based testing on the
calendar application
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24. Scenario Testing
• User personas (real users models)
• Real life examples of how the software will be
used
• Soap Opera Testing (by Hans Buwalda -
www.happytester.com )
24Photo by notfrancois

25. Scenario Testing: Why use it?
• Use your product as it will be used in real life
• Learn about your product
• Verify the claims made in the specification(s)
• Further investigation of known bugs
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26. Scenario Testing: How to
• Choose a Scope
• Define your users
• And their behavior
• Sketch your test cases
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27. Scenario Testing: Example
• Let’s take for example the - www.upb.ro
website
User Action
Teachers Search students, classes, info
Students Look for classes, Master
Programs
College students Admission information,
Alumni
Parents About, Dorms, Financial info
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28. Soap Opera Testing
• It’s all about real life
• Many characters, multiple action plans
• Extreme (but not necessarily)
28http://iubirecainfilme.ro

29. Soap Opera: “Iubire ca in filme”
• “Ioana face aceste sacrificii pentru ca Raluca sa aiba parte de cea
mai buna educatie, la Scoala de fete, singura institutie de acest gen
care are si internat, un loc exclusivist si foarte strict. Oricit de mult
s-ar stradui Ioana, Raluca nu va fi ferita de necazuri care vin odata
cu prima iubire, mai precis atunci cind il cunoaste pe Dragos (Adrian
Nicolae), un tinar student la Stiinte Politice. Insa lucrurile incep sa
se complice cind prietena cea mai buna a Ralucai, Dana (Sabina
Brinduse), se indragosteste tot de Dragos...”
• “Ioana il cunoaste pe Stefan (Dan Bordeianu), fiul unei familii
bogate si intre cei doi se naste o iubire ca in filme. Ea se recomanda
ca fiind psiholog iar el o roaga sa il ajute sa iasa de sub influenta
mamei sale, doamna Elvira Varga (Catalina Mustata). Aceasta este o
femeie dominatoare care vrea sa controleze viata lui Stefan si a
surorii lui, Dana.”
• More on: http://iubirecainfilme.ro/sinopsis.html
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30. Q & A
Catalin Anastasoaie
The Alchemy of Software Testing
http://www.acatalin.ro
• Resources:
– http://www.testingeducation.org/BBST
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