Smarter tests for development of software can save both time and money for the developer

Jun 14, 2013 | Research/Cooperation

In his doctoral thesis ”Quality of Test Design in Test Driven Development”, Adnan Causevic at the School of Innovation, Design and Engineering at Mälardalen University (MDH), investigates the quality of test cases produced in test-driven development.

Adnan Causevic came to Sweden from Bosnia-Herzegovina after studies in his home country. After a guest lecture by Professor Ivica Crnkovic from Mälardalen University, Adnan got to know about the possibilities of doing a PhD abroad, and the choice fell on Sweden and MDH.

Today tests are designed in the first stage by the software developer in connection with the development of the software. The software developer is rarely an expert at testing, and in 70 per cent of the cases they make use of what is known as “positive” testing, which means that the test investigates whether the software does what it has been developed to do. In only 30 per cent of the cases do they make use of “negative” testing, in which one instead investigates whether the software does not do what it should not do. The effect of the choice of tests is investigated in the thesis, and the findings show that only 30% of the bugs are discovered in “positive” testing, whereas 70% are discovered in “negative” testing.

- The earlier you discover bugs in the software the cheaper it becomes for the developer to deal with these; in cases where the bugs aren’t discovered before reaching the customer or the end user, this normally means high costs, says Adnan Causevic.

Adnan Causevic has carried out experiments and investigations assisted by both students at MDH but also in cooperation with the company InfoSys, during a one-month internship in India.

The doctoral thesis has resulted in suggestions as to how one can work from now on with “negative” tests in test-driven development. Software developers will continue to be experts at developing software but still be better able to deal with testing. Organisations will thus be able to develop in a more time- and cost-effective way.

What the future holds in store is not yet decided but Adnan Causevic would very much like to stay in Sweden and would be happy at the prospect of a future at Mälardalen University .