Julie Gardiner - Branch out using Classification Trees for Test Case Design - EuroSTAR 2010
-
Upload
eurostar-software-testing-conference -
Category
Technology
-
view
92 -
download
0
description
Transcript of Julie Gardiner - Branch out using Classification Trees for Test Case Design - EuroSTAR 2010
1 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
EuroSTAR 2010 Branch out using Classification
Trees for test case design
Julie Gardiner Grove Consultants
26 Fallowfield Orton Wistow Peterborough PE2 6UR. UK
Tel +44 7974 141436 email: [email protected]
www.grove.co.uk
© Grove Consultants
Challenges we have as Test Managers
convincing management scope of testing
constant changes in projects
explaining testing to others
obtaining sign off from customers/business
plus many others…
2 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
Challenges we face in test design
resources available time (design and execute) too many tests too few tests maintenance of the tests where to start lack of prioritisation what techniques to use
plan / control
analysis/design
impl / exec
exit / report
closure Classification Trees will focus on these
Hand drill (Equivalence classes)
The technique toolbox
Spanner/Wrench – (State transition testing)
Hammer (Boundary value analysis)
Screwdriver – (Pairwise)
3 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
The power-tool in our toolbox
• variety of tools in one tool • for different jobs
• variable speeds • for different skills
• many functions • sprit level, handle, wrist strap, screwdriver holder etc
• mains and battery pack • provides flexibility
• appeals to all people • a MUST in your toolbox
Power tools are an essential item
4 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
Classification tree is the power tool
a technique that EVERYONE needs
Fundamentals of Classification Trees
1. choose test object e.g. component or system function
2. determine input domain 3. determine relevant factors affecting testing 4. form classifications by partitioning input domain
into classes 5. apply 3. and 4. recursively as appropriate 6. form combination table from classification tree and
identify test cases
5 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
Example – ATM machine
Change pin
Cash Withdrawal
Statement request
Balance enquiry
Another transaction?
Classification tree - business tests (ATM)
type of transaction
3 4
2 1
statement
yes no
change pin
yes no
balance enquiry
no screen print
other
valid invalid no yes no
cash withdrawal
6 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
1.11
Classification tree - system test cash withdrawal
3 4
2
1
receipt?
yes no 100 10
amount
500
multiple of 10
other
invalid
confirm
yes cancel yes no
enough funds?
5
Classification tree – component test
amount
digit
multiple of 10
not multiple of 10
special chars
zero null chars
3 4
2 1
5
length
valid invalid (2 or 3 digits)
<2 >3
7 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
Classification tree – EuroSTAR pricing example
pricing of conference
days at conference
all days none
group discount
yes no
tutorials days chosen
on
date
early bird discount
mon tues none
member supporting org
yes no after
date
3
4
2 1
5
before
date
both one day
The “free battery pack” for flexibility
this power-technique has a free tool, providing: • flexibility • speed • visibility • interoperability with other tools
8 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
Test coverage
Class coverage pricing of conference
days at conference
all days none
group discount
yes no
tutorials days chosen
on
date
early bird discount
mon tues none
member supporting org
yes no after
date
3
4
2 1
before
date
both one day
Every class has been covered with these tests
9 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
Combination coverage pricing of conference
days at conference
all days none
group discount
yes no
tutorials days chosen
on
date
early bird discount
mon tues none
member supporting org
yes no after
date
before
date
both one day
Maximum tests = 144
3 2 3 4 * * * * 2
How can we reduce the test cases?
Test Cases
Test Cases
how?
10 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
What the critics say… isn’t this just Equivalence partitioning
(classes)? what about Boundary Value analysis? how does it fit with other techniques? can you use it in exploratory testing? what about non-functional testing? too many tests are produced (some
unrealistic) can you assign risk? others?
When to use (or not use) CT
11 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
Some of the industries actively using Classification Trees
education
travel
retail
media
medical
financial
communications
airline
insurance
Summary: key points
classification trees is a graphical way of showing test cases
can be applied at any level of testing it could be used in any organization it might complement other testing techniques use it to raise visibility of test cases and
improve maintainability
12 © Grove Consultants UK
Branch out using Classification Trees for test case design
www.grove.co.uk
Thank you!
Julie Gardiner Grove Consultants
26 Fallowfield Orton Wistow Peterborough PE2 6UR. UK
Tel +44 7974 141436 Email: [email protected]
Resources: Free tool: http://www.berner-mattner.com Other tools: Hitex, Razorcat