MuJava: an automated class mutation system

TLDR

Mutation testing is a powerful but traditionally expensive technique for evaluating object‑oriented programs, prompting recent efforts to develop criteria that assess key OO features. This study proposes a cost‑reduction method for mutation testing of OO programs by combining mutant schemata generation and bytecode translation. The method adapts MSG for behavior‑changing mutants and applies bytecode translation to structure‑changing mutants, implemented in a tool that measures speedup against separate compilation. Experiments demonstrate that the approach requires only two compilations and achieves roughly a five‑fold speedup over separate compilation. © 2004 John Wiley & Sons, Ltd.

Abstract

Several module and class testing techniques have been applied to object-oriented (OO) programs, but researchers have only recently begun developing test criteria that evaluate the use of key OO features such as inheritance, polymorphism, and encapsulation. Mutation testing is a powerful testing technique for generating software tests and evaluating the quality of software. However, the cost of mutation testing has traditionally been so high that it cannot be applied without full automated tool support. This paper presents a method to reduce the execution cost of mutation testing for OO programs by using two key technologies, mutant schemata generation (MSG) and bytecode translation. This method adapts the existing MSG method for mutants that change the program behaviour and uses bytecode translation for mutants that change the program structure. A key advantage is in performance: only two compilations are required and both the compilation and execution time for each is greatly reduced. A mutation tool based on the MSG/bytecode translation method has been built and used to measure the speedup over the separate compilation approach. Experimental results show that the MSG/bytecode translation method is about five times faster than separate compilation. Copyright © 2004 John Wiley & Sons, Ltd.