Studying the Impact of CI/CD Adoption on Atoms of Confusion Distribution and Prevalence in Open-Source Projects

Atoms of Confusion (AoC) are indivisible code patterns that may confuse developers when trying to understand them, and that have less confusing equivalent patterns. Previous works suggest it is a good practice to avoid them. While there are studies on AoC relating them to bugs, there is not much about their relationship with the practices of Continuous Integration and Continuous Delivery (CI/CD). Since CI/CD is generally praised as a group of good practices, related to better code being released reliably and faster to clients, there is a possibility that the presence of CI/CD would also impact the presence of AoC, possibly making them less prevalent since they can be problematic to development processes. To clarify this relationship, we analyzed 10 open-source long-lived Java libraries and 10 open-source Java projects for Android, to see if there was any difference in the AoC rate, diffusion, and density before and after the implementation of CI/CD when comparing each project, the average total. We also analyzed the atoms separately, checking for the most and least prevalent. Our results show the metrics have considerably changed for all projects when checked separately, and less so on average, but we could not find a statistically relevant relationship between most of these changes and CI/CD. We found a significant relation when checking the growth rate on one of the metrics. We also found that the most prevalent atom is the Logic as Control Flow, and the least is the Arithmetic as Logic.