Week 9

Question 1

What is the difference between validation testing and defect testing?

Answer 1

Validation testing: ensures system meets clients expectations

Defect testing: detects defects and problems

Question 2

What is the difference between black and white box testing?

Answer 2

Black-box: from outside, just public methods (user view)

White-box: from inside, considering all aspects (programmer view)

Question 3

what are 3 examples of algorithmic faults?

Answer 3

Missing initialization

Incorrect branching condition

Missing test for null

Question 4

What is an example of a mechanical fault?

Answer 4

Operating temperature outside equipment specification

Question 5

What are 3 examples of an error?

Answer 5

Null reference error

Concurrency errors

Exceptions

Question 6

What are the 3 levels of testing?

Answer 6

Level 1 - Test modules (classes), programs and “suites”

Level 2 - “Alpha” - Execute programs in simulated environment and test input and output

Level 3 - “Beta” - Test in a live user environment and test for response times, performance under load and recovery from failure

Question 7

What are the 6 types of test in the hierarchy?

Answer 7

Unit test

Integration test

Function test

Performance test

Acceptance test

Installation test

Question 8

The only type of testing that is not undertaken by the programmers is _____ testing.

This is done by _____________.

Answer 8

Acceptance testing

The client

Question 9

What is the difference between unit testing and integration testing?

Answer 9

Unit testing tests individual methods with stubs for any interfaces - white box

Integration testing tests a system of integrated components up to the whole program - black box

Question 10

What are the two approaches to integration testing?

Answer 10

Top-down testing - start with high level and replace individual components with stubs where appropriate

Bottom-up testing - Integrate individual components, replacing the stubs until the complete system has been tested

Question 11

What is functional testing?

Answer 11

Tests each function against its functional requirement. Not concerned with internals as long as it works.

Question 12

What is performance testing?

Answer 12

Test the program’s use of resources and time

Question 13

What is stress testing?

Answer 13

Test the system beyond its maximum design load

See how it copes/recovers if things fail

Question 14

What is regression testing?

Answer 14

Rerunning all previous tests after applying changes

Question 15

What is acceptance testing?

Answer 15

Tests against the client’s requirements in a test facility

Question 16

What is installation testing?

Answer 16

Execute in target environment with configuration etc.

Re run all previous tests

Question 17

What is the goal of unit testing and integration testing?

Answer 17

Unit testing - to ensure the component is correctly coded

Integration testing - test the interfaces between the subsystems

Question 18

What type of behaviour is the focus of black box testing?

Answer 18

I/O behaviour - testing to ensure input gives correct output

Question 19

How can the number of test cases in black box testing be reduced?

Answer 19

Equivalence partitioning - dividing inputs into equivalence classes and testing from each class

e.g. one negative number is enough to test that negative numbers work

Question 20

If an input is valid across a range of values, 3 types of value should be tested:

Answer 20

Below the range

Within the range

Above the range

Question 21

What are the 4 elements in unit testing

Answer 21

Cases

Driver

Oracle

Stubs

Question 22

What are the components of a test case?

Answer 22

Set of input data

Expected results

Question 23

What are the steps in test driven development?

Answer 23

Add a test

Run test to ensure it fails

Update functional code to ensure it passes

re run and keep updating functional code until tests pass

refactor and move on

Question 24

What are the benefits of Test driven development?

Answer 24

Shortens programming feedback

Provides detailed executable specifcations

promots high quality code

provides concrete evidence the code works

requires developers to prove it with code

provides finely grained feedback within minutes

ensures design is clean

supports evolutionary development

Question 25

Test driven development implies ________________ methodology