ISTQB FOUNDATION 4.0 | Tutorial 33 | State Transition Testing | Test Case Design Techniques | CTFL
Summary
TLDRThis tutorial delves into state transition testing, a blackbox technique for analyzing software requirements with control flows or state definitions. It emphasizes the use of state transition diagrams (STDs) to visualize system states and valid transitions, excluding invalid ones. The instructor illustrates how to identify valid and invalid transitions to derive comprehensive test cases, using examples like a bank card PIN entry system and the states of water. The video aims to prepare viewers for ISTQB Foundation level certification, focusing on understanding the technique rather than memorization, with sample exam questions to solidify the concepts.
Takeaways
- π The tutorial is focused on ISTQB Foundation level certification, specifically chapter 4.2 on blackbox test techniques.
- π The last technique discussed in the chapter is State Transition Testing, which is used for requirements with control flow or defined states and transitions.
- π State Transition Testing is applicable for transactional or functional requirements where actions lead to the next state of an application.
- π‘ An example given is accessing an account which involves swiping a card and entering a PIN, with different outcomes based on the number of incorrect attempts.
- π Straight Transition Testing is a technique used to visually represent requirements and derive the minimum number of test cases.
- π State Transition Diagram (STD) is a key tool in State Transition Testing, showing all valid transitions between states without invalid transitions.
- π« Invalid transitions are not displayed in the STD, but they can be identified by missing pairs of transitions between states.
- π The technique involves identifying valid and invalid transitions to ensure full test coverage, including both valid and invalid test cases.
- π At the Foundation level, exam questions will provide diagrams and ask about valid and invalid test cases based on those diagrams.
- π The tutorial also provides examples of exam questions to illustrate what candidates can expect and how to approach them.
- π The importance of understanding the concepts behind State Transition Testing is emphasized, as it is not just for passing the exam but also for practical application.
Q & A
What is the main focus of the tutorial in the provided script?
-The tutorial focuses on the ISTQB Foundation level certification, specifically discussing state transition testing, which is a blackbox test technique used to analyze requirements with control flow or state transitions.
What is state transition testing?
-State transition testing is a technique used to exhibit the various states of a scenario or system and display the possible transitions between them. It is typically represented using a state transition diagram (STD), which shows all valid transitions and helps in deriving test cases.
What is a state transition diagram (STD)?
-A state transition diagram (STD) is a pictorial representation that shows the various states of a system or scenario and the valid transitions between them. It does not display invalid transitions, which are identified by missing pairs of transitions between states.
How are invalid transitions identified in state transition testing?
-Invalid transitions are identified by looking for missing pairs of transitions between two states in the STD. If a transition is not represented in the diagram, it is considered invalid and is not part of the system's behavior.
What is the purpose of using straight transition testing?
-Straight transition testing is used to understand and deflect the requirements into a pictorial way, which helps in deriving the minimum number of test cases that cover both valid and invalid transitions.
Can you provide an example of state transition testing from the script?
-An example given in the script is an ATM machine where entering a correct PIN on the first attempt takes you to the main menu, while incorrect attempts allow for two more tries, after which the card is rejected and further access is denied.
What is the significance of valid and invalid test cases in state transition testing?
-Valid test cases ensure that the system behaves as expected for all possible transitions, while invalid test cases verify that the system correctly handles transitions that should not occur, thus ensuring the system's robustness and reliability.
How does the tutorial suggest approaching exam questions related to state transition testing?
-The tutorial suggests that exam questions will provide a state transition diagram, and candidates should read the diagram to identify valid and invalid transitions and answer questions based on that information.
What are some of the characteristics of state transition testing discussed in the tutorial?
-Some characteristics discussed include the use of an STD to represent valid transitions, the identification of invalid transitions by missing pairs, and the application of this technique to derive comprehensive test cases.
How does the tutorial explain the process of deriving test cases from a state transition diagram?
-The tutorial explains that by examining the STD and identifying all valid transitions (represented by arrows) and invalid transitions (missing pairs of arrows), one can derive a comprehensive set of test cases that cover all possible scenarios.
What is the difference between state transition testing at the Foundation level and the advanced level, as mentioned in the tutorial?
-At the Foundation level, candidates are expected to interpret given diagrams and answer questions about valid and invalid transitions. At the advanced level, candidates may be asked to draw the diagrams themselves and then derive the number of test cases.
Outlines
π Introduction to State Transition Testing
This paragraph introduces the concept of state transition testing, a blackbox testing technique used for analyzing software requirements with control flow or state definitions. It explains that this technique is particularly useful for applications where actions can lead to different states, such as a banking application requiring a card swipe and PIN entry. The paragraph uses the example of a PIN entry system to illustrate how state transition testing works, emphasizing the importance of understanding the transitions between states and the creation of test cases based on valid and invalid transitions. The technique of straight transition testing is mentioned as a method to visualize requirements and derive the minimum number of test cases.
π Characteristics and Techniques of State Transition Testing
The second paragraph delves into the characteristics of state transition testing, focusing on the use of state transition diagrams (STDs) to represent the various states of a system and the transitions between them. It clarifies that STDs only show valid transitions, excluding invalid ones, and discusses how to identify invalid transitions by looking for missing pairs in the diagram. The paragraph provides a hypothetical example with three states (S1, S2, S3) to demonstrate how to determine valid and invalid transitions, resulting in a total of six test cases, four valid and two invalid. It also touches on the expectations of the ISTQB Foundation level certification exam, which involves reading and interpreting diagrams rather than creating them.
π Sample Exam Questions and Understanding State Transition Testing
The final paragraph presents sample exam questions to illustrate how state transition testing concepts might be applied in a real-time scenario. It uses the analogy of a water cycle to explain the technique further and then discusses how to identify valid and invalid test cases based on a given state transition diagram. The paragraph emphasizes the importance of understanding the technique and its application in deriving test cases, rather than merely memorizing for an exam. It also mentions that while the Foundation level exam will not require drawing diagrams, the advanced level will, and encourages viewers to grasp the underlying concepts for practical application.
Mindmap
Keywords
π‘ISTQB Foundation Level Certification
π‘Test Analysis and Design
π‘Blackbox Test Techniques
π‘State Transition Testing
π‘Control Flow
π‘State Transition Diagram (STD)
π‘Valid Transitions
π‘Invalid Transitions
π‘Straight Transition Testing
π‘Test Cases
π‘Pictorial Representation
Highlights
Introduction to ISTQB Foundation Level Certification tutorial focusing on Test Analysis and Design.
Exploring Blackbox Test Techniques, specifically State Transition Testing.
Understanding State Transition Testing through the context of control flow and state transitions in requirements.
The importance of pictorial representation for requirements using State Transition Diagrams (STD).
Explanation of how to identify valid and invalid transitions in a State Transition Diagram.
The significance of not displaying invalid transitions in STD for maintaining system behavior integrity.
Technique of Straight Transition Testing for deriving minimum number of test cases.
Illustration of State Transition Testing with a real-world example of a bank account access system.
Detailed walkthrough of a hypothetical State Transition Diagram with three states, S1, S2, and S3.
Identification of valid and invalid transitions in the example diagram and their implications for testing.
Explanation of how missing transitions in the diagram indicate invalid test cases.
Foundation Level examination expectations regarding reading and interpreting State Transition Diagrams.
Sample exam questions to demonstrate the application of State Transition Testing in a testing scenario.
Discussion on how to approach exam questions involving identifying valid and invalid test cases from a diagram.
Use of a water state transition example to clarify the concept of valid and invalid transitions.
The importance of understanding the technique's practical application beyond just passing the exam.
Encouragement for continuous learning and application of the State Transition Testing technique.
Transcripts
Hello friends and greetings for the day
welcome back to another tutorial on
istqb Foundation level certification we
are in chapter 4 talking about test
analysis and design and continuing ahead
with our same segment that is 4.2
blackbox test techniques and as a part
of today's tutorial we'll be talking
about the last technique under this
category that is State transition
testing
well when it comes to the state
transition testing of course this is one
of its kind again just like decision
table testing here we talk about the
requirements which has any sort of
control flow involved or have a
definition between the different states
and the transitions possible so mainly
the requirements can be defined in terms
of transactional way or functional way
where uh an action can be taken to the
next state of the application where
there are only possible ways to reach
out a point in simple words if I have to
say for example in order to access your
account you will have to swipe in your
card enter the pin but entering the pin
could be a little tricky thing right you
can enter the pin right in very first
attempt and you'll be taken to the main
menu option if in case your uh first pin
attempt is wrong the loop will continue
there and you will be allowed to do two
more attempts uh if in case wrong and
third attempt it will just reject your
card and at the same time you will not
be able to continue further so in this
case to understand and deflect this
requirement into a pictorial way and
then derive the minimum number of test
cases we make use of a technique called
as straight transition testing so I do
understand again theoretically it could
be very difficult to make out things but
of course when it comes to the reality
with some examples it would make more
sense so yes let's quickly have a look
on what state transition testing is
trying to let us know about its
characteristics and the technique and
let's see how the sample exam question
questions would look like and what we
have to answer so the very first thing
here to talk about State transition
testing is it basically exhibits the
various states of a scenario or system
and displays the possible transitions
between them now the most important
thing here to understand is that state
transition testing is done with help of
State transition diagram which is
basically a pictorial representation and
it displays the various states of the
system or a scenario and only the
possible transitions between them the
reason when we say possible transitions
only is just because the invalid
transitions should not be displayed
because if it is displayed it becomes
valid right let's have a look again so
when we talk about the state transition
diagram that's what is the exhibition of
this pictorial representation however
the technique is called as state
transition testing now an STD certainly
shows all valid transitions only so it
does not represent any invalid
transition however there is a way to
figure out what are the invalid
transitions so that you can derive full
coverage that is valid plus invalid test
cases right so how to do that so in case
when we talk about the STD it consists
of a pair of transition between two
states just like in the diagram below so
if you see this is just a hypothetical
example uh we have three different
states S1 S2 S3 now in this case S1 uh I
can go from S1 to S2 S2 to S3 and same
way I can come back from S3 to S2 and S2
to S1 so there are four transitions on
the picture right here and uh four of
them are valid the all four a b c d all
the four are valid here now in this case
we totally understand that the there are
four transitions which are actually
possible as per the given scenario you
may certainly have a question that why
I'm not going from S1 to S3 that's also
possible no that's your prediction you
have to go as for the requirement if
requirement says the user should not be
able to go from S1 to S3 directly then
that becomes invalid for you that's the
behavior right you are still in blackbox
testing techniques so in this case
that's how you identify that what are my
invalid test cases but to make it more
technical from the require technique
point of view of course the technique
says uh STD should consist of pair of
transition between any two states so S1
to S2 you can see there is a pair like a
and d so it goes S1 to S2 S2 to S1 same
way between S2 and S3 you have pair of
transitions onward and return but
between S1 and S3 the pair is missing
and that's how you identify the number
of invalid test cases so if the pair is
missing between two sites then the
missing transition or transitions is or
are called as invalid transitions so
it's not necessary that both the
transitions may be missing in all the
cases sometimes just one will be missing
one will be there so only the missing
transitions are referred to as invalid
valid so in our below example the
diagram here the S1 to S2 and S3 a b c d
are four valid and two invalid because
S1 to S3 and S3 to S1 is not picturized
here imagining or understanding us that
it is invalid so in that context we have
six test cases and U four valid two
invalid however that's not what they
will be asking you to do in the
examination at Foundation level at
Foundation level they expect you to read
the diagram and based on that pick up
the right options what they ask you
about so they can ask you questions
about the test cases they can ask you
the questions about the characteristics
what we have dis displayed here on the
screen uh and discussed about that so
let's quickly take up some sample
questions from here but before that
another quick example to talk about that
what a streight tation diagram could be
all about so talking about a quick
example here so if you see uh this is
how exactly the technique works so a
street transition diagram for a water is
being considered and again I'm not not
talking about literally something in
different conditions you may come up and
say that oh you know we can talk about
dry ice and that can go to Vapors
directly so let's keep it simple and
static because we talking about
techniques not talking about how to test
water and dry ice okay so taking that
into account if you see ice uh I can
heat it and get the water then water I
can boil it and I get it the vapor a
vapor I can condensate and get water
back and if I freeze water I get get ice
back but in this case again the four
valid transitions are only possible the
other two that is ice to vapor and Vapor
to ice in normal conditions are not at
all possible Right in that context we
don't draw that's the reason I have just
pictorially presented in a black color
bigger arrows just to say that hey these
are not actually there but just to
display in order to talk about I'm
presenting it okay so it's that these
are just two invalid uh test cases and
they generally do not get displayed I
displayed because I wanted to talk about
it okay so these two are invalid and a b
c d are the valid transition however we
draw a table like this and that's how we
get our test cases from the scenario so
let's take some exam questions to
understand what could be expected in the
real time
scenario so right here if you notice we
got uh very first question to talk about
question says based on the given State
transition diagram of a switch which of
the following test cases is in valid now
invalid is what is the ask here and the
most important thing is you have to
follow the diagram and understand that
if something is not being drawn that
means the transition is missing between
two states those are the one which are
called as invalid so let's have a look
at the quick diagram here if you see
this is a switch diagram so I have on to
off off to on then when I turned it on
it got burnt and it became faulty switch
and the loop below the fault that is an
arrow turning around to The Fault itself
is basically a loop that means the
faulty switch will remain faulty forever
and it will never come back to any other
state so that Loop basically represents
that so I have S1 S2 S3 but with
different names so the question is which
one of this is
invalid so option A says off to on of
course that is in the diagram so it is
valid that means a user can do that on
to off is possible a user can certainly
uh turn off a switch C fault to on of
course fault to on is not displayed here
here so at any point of time based on
the given information that's a invalid T
case Okay false to on is not displayed
so it is invalid there's no return path
as for the diagram and the option D says
onto fault which is obviously written
there so it's a line representing
between on and fault so it is a valid
transition so put together the right
answer here is D sorry C that is Fault
to on is not a valid test case which
means invalid let's also look at one
more example here which would give you
double confidence to be sure that what
other types of questions can be asked so
additionally one more point to add here
that the pictures will be represented
always in the examination questions and
then they will be asking you questions
so do not forget that you have you don't
have to draw the diagram okay they will
not not ask you to draw however the same
thing will be asked to you in the
advanced level in advanced level they
will ask you to draw the diagram and
then derive the number of test cases but
now they will just ask you what is valid
what is invalid at this point of time so
let's quickly look at the next one and
the next question here is talking about
similar thing but with different example
so given the following straight
transition table which of the test cases
below will cover the following series of
State transitions so series is given to
you they want you to go through S1 s0 S1
S2 s0 again so if you look at the
diagram we have s0 S1 S2 and we have
transitions named there that is a b c d
so they want to follow S1 to s0 then s 0
to S1 S1 to S2 and S2 to s0 so all you
have to do is pick up each of these
options ABC D and put it on the diagram
and see which one is actually fulfilling
that Series so if I look at the very
first option A says da a b c so okay
again S1 to s0 is D that's true s0 to S1
is a S1 to S2 is B and S2 to s0 is C
which is absolutely right but let's look
at the other options AB C D no AB is
correct s0 to S1 S1 to S2 but that's not
what they are asking for okay um C they
say d a which is also possible but
that's not what they're asking because
their Series has been clearly defined
they want S1 to s0 S1 s0 to S1 and then
S1 to S2 and after that S2 to s0 as well
so just daab alone will not do it you
need the C as well okay and same way
with the option d a b c this is also
possible as for the diagram but that's
not the ask so it's very very important
for you to understand what exactly are
they asking you and more importantly you
need to understand what is the technique
all about right what a picture basically
defines what these diagrams basically
represent and how this adds value Al
together towards preparing minimum
number of test cases please do not try
to do this mathematically try to
understand the concepts because you
don't just have to pass the exam you
have to apply and understand this
technique that why are we even using
this as a technique right so that should
make sense at the end of the day so
that's all from this particular tutorial
team should you have anything else feel
free to comment below I'm always there
to address your queries and answer them
well till then keep learning keep
exploring keep understanding the context
thanks for watching the video team and
happy
[Music]
learning
Browse More Related Video
CH05.L05 . BBT-4-state transition
ISTQB FOUNDATION 4.0 | Tutorial 30 | Equivalence Partition | Black Box Test Techniques | CTFL
ISTQB FOUNDATION 4.0 | Tutorial 31 | Boundary Value Analysis | Test Techniques | ISTQB Tutorials
Software Testing Tutorial #34 - Equivalence Partitioning in Testing
ISTQB FOUNDATION 4.0 | Tutorial 48 | Test Execution Schedule | Test Prioritization | CTFL Tutorials
ISTQB FOUNDATION 4.0 | Tutorial 32 | Decision Table Testing | Test Case Design Techniques | CTFL
5.0 / 5 (0 votes)