Test design techniques

1. Test design techniques

Ryzhkov Ivan

2.

Test design –
the process of transforming general
testing objectives into tangible test
conditions and test cases.

3. Test design techniques:

Equivalence Partitioning
Boundary Value Analysis
Cause/Effect
Error Guessing
Decision tables
State transition

4. Equivalence Partitioning

Equivalence Partitioning (EP, also, called Equivalence
Class Partitioning) is a software testing technique that
divides the given condition into partitions and one input
data from each partition can be chosen for testing.
EP can reasonably reduce the number of your test
cases. It can be used at all levels of testing – unit,
integration and system test levels.

5. Equivalence Partitioning

Example:
You have a range of admissible values from 0 to
10. You should be choose one of valid value, for
example 3 and one invalid value - 11

6. Boundary Value Analysis

Boundary Value Analysis (BVA) is the process of testing
between extreme ends or boundaries between partitions
of the input values.
Analysis Boundary Values can be applied to fields,
records, files, or to any kind of entities with constraints.

7. Boundary Value Analysis

Example:
If we take the example above (from EP), as the
values for positive testing, we select the minimum and
maximum boundaries (0 and 10), and the values are
larger and smaller than the boundaries – negative
testing (-1 and 11)

8. Cause/Effect

Cause Effect( or Cause Effect Graph ) is a black box
testing technique that graphically illustrates the
relationship between a given outcome and all the factors
that influence the outcome.
Cause 1
Example of the solution of problem for a
triangle:
Cause 3
EFFECT
Cause 2
Cause 4
Couse 1:
Effect 1:
Couse 2:
Effect 2:
Cause 3:
Effect 3:
Side “x” is less than sum of “y” and “z”
Not a triangle
Side “x” is equal to side “y”
Equilateral triangle
Side “z” is less then sum of “x” and “y”
Isosceles triangle.

9. Error Guessing

Error guessing is a testing technique that makes use of a
tester's skill, intuition and experience in testing similar
applications to identify defects that may not be easy to
capture by the more formal techniques. It is usually done
after more formal techniques are completed.
Example:
Divide by zero
Entering blank spaces in the text fields
Pressing submit button without entering values.
Uploading files exceeding maximum limits.

10. Decision Tables

Decision tables are a precise yet compact way to model
complex rule sets and their corresponding actions.
Example: Printer troubleshooter

11. Decision Tables

Condition
Action
Printer prints
A red light is flashing
Printer is recognized by
computer
Check the power cable
R1
N
Y
N
R2
N
Y
Y
Check for paper jam
R4
N
N
Y
R5
Y
Y
N
R6
Y
Y
Y
R7
Y
N
N
x
x
Check the printercomputer cable
Ensure printer software is x
installed
Check/replace ink
R3
N
N
N
x
x
x
x
x
x
x
x
x
x
R5
Y
N
Y

12. State Transition

State Transition testing is defined as the testing
technique in which changes in input conditions causes
state changes in the Application Under Test(AUT).
State Transition Testing Technique is helpful where
you need to test different system transitions.
State transition testing – is a black box test design technique in which test cases are
designed to execute valid and invalid state transitions [ISTQB]

13. State Transition

Example:
You have a flight reservation login screen. You should be to enter correct
agent name and password in the login screen to access the flight reservation.