Characterising Developer Sentiment in Software Components: An Exploratory Study of Gentoo

Collaborative software development happens in teams, that cooperate on shared artefacts, and discuss development on online platforms. Due to the complexity of development and the variety of teams, software components often act as effective containers for parallel work and teams. Past research has shown how communication between team members, especially in an open-source environment, can become extremely toxic, and lead to members leaving the development team. This has a direct effect on the evolution and maintenance of the project in which the former members were active in. The purpose of our study is two-fold: first, we propose an approach to evaluate, at a finer granularity, the positive and negative emotions in the communication between developers; and second, we aim to characterise a project's development paths, or components, as more or less impacted by the emotions. Our analysis evaluates single sentences rather than whole messages as the finest granularity of communication. The previous study found that the high positivity or negativity at the sentence level may indirectly impact the writer him/herself, or the reader. In this way, we could highlight specific paths of Gentoo as the most affected by negative emotions, and show how negative emotions have evolved and changed along the same paths. By joining the analysis of the mailing lists, from which we derive the sentiment of the developers, with the information derived from the development logs, we obtained a longitudinal picture of how development paths have been historically affected by positive or negative emotions. Our study shows that, in recent years, negative emotions have generally decreased in the communication between Gentoo developers. We also show how file paths, as collaborative software development artefacts, were more or less impacted by the emotions of the developers.