What is White Box Testing?
White box testing is a testing technique, that examines the program structure and derives test data from the program logic/code. The other names of glass box testing are clear box testing, open box testing, logic driven testing or path driven testing or structural testing.
White Box Testing Techniques:
- Statement Coverage – This technique is aimed at exercising all programming statements with minimal tests.
- Branch Coverage – This technique is running a series of tests to ensure that all branches are tested at least once.
- Path Coverage – This technique corresponds to testing all possible paths which means that each statement and branch is covered.
Calculating Structural Testing Effectiveness:
Statement Testing = (Number of Statements Exercised / Total Number of Statements) x 100 % Branch Testing = (Number of decisions outcomes tested / Total Number of decision Outcomes) x 100 % Path Coverage = (Number paths exercised / Total Number of paths in the program) x 100 %
Advantages of White Box Testing:
- Forces test developer to reason carefully about implementation.
- Reveals errors in “hidden” code.
- Spots the Dead Code or other issues with respect to best programming practices.
Disadvantages of White Box Testing:
- Expensive as one has to spend both time and money to perform white box testing.
- Every possibility that few lines of code are missed accidentally.
- In-depth knowledge about the programming language is necessary to perform white box testing.