Test Design Techniques

Question 1

Types

Answer 1

Specification based(black box)
Structure based(white box)
Experience based

Question 2

Why use techniques

Answer 2

To select tests effective at finding faults and efficient

Question 3

Specification based

Answer 3

View software as a black box with uno it’s and outputs but don’t examine how the system is structured. Concentrate on what software does not how it does it. Contains functional and non functional.
Use case testing
Decision table testing

Question 4

Structure based

Answer 4

Requires knowledge of how software works. Uses internal structure of software to derive test cases

Question 5

Experience based

Answer 5

Use people knowledge to determine test conditions and cases. Use both technical and business people as they have different perspectives. Can provide insights into high risk areas.

Question 6

Equivalence partitioning

Answer 6

Dividing a set of test conditions into groups that can be considered the same, system will treat them equivalently
When we have partition we choose one condition from partition to test
Result considered representative of complete partition

Question 7

Valid and invalid

Answer 7

Invalid partition values can be entered by user but they are not expected input by system
Software should be able to correctly handle values from invalid partition by displaying appropriate error message

Question 8

Selecting tests from partitions

Answer 8

Select any value in the range , every value treated same way

Question 9

Deriving test cases

Answer 9

Assign unique identifier to each equivalence class
Until all valid equivalence classes have been covered by at least one test case, write a new test case covering as many equivalence classes as possible
Until all invalid equivalence classes have been covered write a test case that covered one and only one of the uncovered invalid equivalence classes
For each test case annotate it with the equivalence identifiers it covers

Question 10

Equivalent classes partitioning problems

Answer 10

Doesn’t always define expected output for invalid test cases
Strongly typed languages eliminate the need for consideration of some invalid inputs

Question 11

Boundary value analysis

Answer 11

Experience shows more faults at boundaries of equivalence partitions where partitions are continuous
Test cases just below and above boundary find faults