Download Implementation of a Transformation Algorithm

Kiran Lakhotia
MSc Individual Project Report September 2005
Abstract
Metaheuristic search techniques are the preferred method for automatically generating good
quality test data for structural testing. However these techniques fail in the presence of flag
variables because they turn them into a random search. A testability transformation has been
developed to address the problem caused by loop assigned flags in particular, as they have
not been included in other solutions to the flag problem. The transformations convert
predicates containing loop assigned flags into flag free equivalents, while preserving test data
adequacy.
Previous work has shown the effectiveness of the transformations when used in conjunction
with a genetic algorithm to generate test data. However, no research has been done to
investigate the extend by which the transformation increase the size of a program.
The tool developed as part of this project is used to evaluate the transformations with respect
to any increase in size, measured in lines of code. In total five ‘real world’ programs
containing loop assigned flags were transformed by the tool. The paper presents empirical
data showing that the increase in size is not highly statistically significant. The paper also
presents an empirical study, showing that the ability of the tool to detect loop assigned flags in
‘real world’ code is around 94 percent.
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