Investigating code reading techniques for novice inspectors: an industrial case study

Code inspection is believed to be an effective technique to remove defects and improve software quality. However, the adoption of code inspection in industry is far less than it should be, which may lead to many novice inspectors in industry. For these novice inspectors, a suitable reading technique should be of the first step to begin this quality journey. While reports indicated that Checklist-Based Reading (CBR) and Ad Hoc Reading (AHR) had been the most adopted inspection techniques in industry, we deem it is necessary to investigate these two techniques first. In this paper, we present a case study of the adoption of code reading techniques in one small-sized software company. In this study, five engineers used different techniques (i.e., CBR vs. AHR) to read source code in 20 modules. Both quantitative data and qualitative data are collected during the case study. Initial analysis of these data indicates that industrial novice inspectors using CBR tended to have a lower reading speed than those using AHR. Both techniques could help these novice inspectors to remove a certain portion of defects during code review, and compared to AHR approach, CBR may help them find larger percentage of defects. However, there still exist several issues, for example, missing large portion of review-removable defects could not be avoided for novice inspectors. What's more, CBR may limit reviewers' ability to find defects outside the checklist, and to establish effective checklist remains a big challenge for novice inspectors. Besides, both internal factors (e.g., faith in inspection to achieve high quality) as well as external factors (e.g., schedule pressure) may also impact novice inspectors to adopt code reading.