Page 192 - DCAP405_SOFTWARE_ENGINEERING

Unit 11: Testing Strategies

method. One has to use a mixture of different methods so that they aren’t hindered by the Notes
limitations of a particular one. Some call this “gray-box” or “translucent-box” test design, but
others wish we’d stop talking about boxes altogether. White-box test design allows one to peek
inside the “box”, and it focuses specifically on using internal knowledge of the software to guide
the selection of test data.

Did u know? What are synonyms of White box testing?
Synonyms for white-box include: structural, glass-box and clear-box.

Types of White Box Testing

The following types of white box testing exist:
Code coverage: creating tests to satisfy some criteria of code coverage. For example, the test
designer can create tests to cause all statements in the program to be executed at least once.
Mutation testing methods
Fault injection methods.
Static testing: White box testing includes all static testing.

Code Completeness Evaluation

White box testing methods can also be used to evaluate the completeness of a test suite that was
created with black box testing methods. This allows the software team to examine parts of a
system that are rarely tested and ensures that the most important function points have been
tested.
Two common forms of code coverage are: function coverage, which reports on functions executed
and statement coverage, which reports on the number of lines executed to complete the test.
They both return coverage metric, measured as a percentage.

Grey Box Testing

In recent years the term grey box testing has come into common usage. This involves having
access to internal data structures and algorithms for purposes of designing the test cases, but
testing at the user, or black-box level.
Manipulating input data and formatting output do not qualify as grey-box because the input and
output are clearly outside of the black-box we are calling the software under test. This is
particularly important when conducting integration testing between two modules of code written
by two different developers, where only the interfaces are exposed for test.

Notes Grey box testing may also include reverse engineering to determine, for instance,
boundary values or error messages.

LOVELY PROFESSIONAL UNIVERSITY 185