Open-Source Software (OSS) projects have adopted various automations for repetitive tasks in recent years. One common type of automation in OSS is bots. In this exploratory case study, we seek to understand how the adoption of one particular bot (ASFBot) by the Apache Software Foundation (ASF) impacts the discussions in the issue-trackers of these projects. We use the SmartShark dataset to investigate whether the ASFBot affects (i) human comments mentioning pull requests and fixes in issue comments and (ii) the general human comment rate on issues. We apply a regression discontinuity design (RDD) on nine ASF projects that have been active both before and after the ASFBot adoption. Our results indicate (i) an immediate decrease in the number of median comments mentioning pull requests and fixes after the bot adoption, but the trend of a monthly decrease in this comment count is reversed, and (ii) no effect in the number of human comments after the bot adoption. We make an effort to gather first insights in understanding the impact of adopting the ASFBot on the commenting behavior of developers who are working on ASF projects.

Self-Admitted Technical Debt (SATD) represents the admission, made through source code comments or other channels, of portions of a program being poorly implemented, containing provisional solutions or, in general, simply being not ready yet. To better understand developers' habits in SATD annotation, and possibly support their exploitation in tool support, this paper provides an in-depth analysis of the content provided in SATD comments, and the expressed sentiment. We manually inspect and classify 1038 instances from an existing dataset, grouping them along a taxonomy composed of 41 categories (of which 9 top-level ones), identifying their sentiment, and the presence of external references such as author names or issue IDs. Results of our study indicate that (i) the SATD content is crosscutting along life-cycle dimensions identified in previous work, (ii) comments related to functional problems or on-hold SATD are generally more negative than poor implementation choices or partially implemented functionality, and (iii) despite observations from previous literature, only a minority of SATD comments leverage external references.

Swift is a new programming language developed by Apple as a replacement to Objective-C. It features a sophisticated error handling (EH) mechanism that provides the kind of separation of concerns afforded by exception handling mechanisms in other languages, while also including constructs to improve safety and maintainability. However, Swift also inherits a software development culture stemming from Objective-C being the de-facto standard programming language for Apple platforms for the last 15 years. It is, therefore, a priori unclear whether Swift developers embrace the novel EH mechanisms of the programming language or still rely on the old EH culture of Objective-C even working in Swift.