SEVEN PRINCIPLES OF SOFTWARE TESTING- Mamunur Rashid (CSE 10,IUT)

Software testing procedures are modernized day by day. Some basic principles of testing have also been set. These principles can be said as a basic guideline for both, testing and coding based on theoretical ideas and practical experience.

7 principles Testing shows presence of errors Exhaustive testing is not possible Early testing Defect clustering Fading effectiveness Testing depends on context False conclusion: no errors equals usable

system

Testing shows presence of errors

Testing proves the presence of errors It is important to design test cases which

find defects as many as possible.

Exhaustive testing is not possible

It is impossible to test all possible combinations of input cases, data and sceneries.

Risk and priorities are used to concentrated on the most important aspects of testing.

Early testing Prepare testing for each level of

development cycle i.e. it’s important to test early and regularly.

When defects are found earlier in the lifecycle, they are much easier and cheaper to fix these.

Defect clustering

There is no equal distribution of errors within one test object.

The place where one error occurs, it’s likely to find some more.

It’s more like 80-20 Pareto Principle.i.e.20 percent of the defects causing 80 percent of the problems. 

Fading effectiveness

Same test won’t work for long time (Pesticide Paradox).

When any modification is done, the regression testing is necessary.

Testing depends on context

Different methods, techniques, types of testing is related to the type and nature of application.

False conclusion: no errors equals usable system

Absence of error fallacy. Just because testing didn’t find any

defect in the software doesn’t mean the software is ready to be shipped.

User requirements should be matched.