Improving test adequacy assessment by novel JavaScript mutation operators

Software testing is an essential process to verify that software meets its specifications and to detect faults. Mutation testing is an effective software testing technique to assess the adequacy of test suite. A lot of research has been done on mutation testing and number of mutation operators are proposed for Java and other programming languages. However, mutation operators for Java Script language are few in number as compared to mutation operators for other programming languages. The focus of our research is on mutation operators. Nowadays, Java Script is regressively used in front end development of web applications. To check the adequacy of test suite of Java Script applications, mutation testing is an appropriate approach. These Java Script mutation operators are used to seed faults in Java Script source programs. Currently available mutation operators cover some of the specific Java Script features as there exists some specific Java Script features that are not yet addressed and require more mutation operators. In this paper, we propose a set of new Java Script mutation operators to address features like variable scope, variable type etc., that are not covered by existing operators. We implemented these mutation operators in a tool called Mutant Tracer.