Detecting Defects with an Interactive Code Review Tool Based on Visualisation and Machine Learning

Code review is often suggested as a means of improving code quality. Since humans are poor at repetitive tasks, some form of tool support is valuable. To that end we developed a prototype tool to illustrate the novel idea of applying machine learning (based on Normalised Compression Distance) to the problem of static analysis of source code. Since this tool learns by example, it is rivially programmer adaptable. As machine learning algorithms are notoriously difficult to understand operationally (they are opaque) we applied information visualisation to the results of the learner. In order to validate the approach we applied the prototype to source code from the open-source project Samba and from an industrial, telecom software system. Our results showed that the tool did indeed correctly find and classify problematic sections of code based on training examples.