一句话:大规模实证研究开源游戏开发中 multi-PR issue 的普遍性、成因分类及解决时间与开发成本,揭示其相对单 PR issue 的显著差异。
视频游戏追求沉浸式体验,其 issue 报告(如 bug 报告)常需跨多个 pull request(PR)迭代修复,但此类 multi-PR issue 尚未被充分研究。本文对开源游戏开发中的 multi-PR issue 进行大规模实证研究,分析其普遍性,归纳为何一个 issue 会关联多个 PR 的分类体系,并将其解决时间与开发投入同 single-PR issue 比较。结果显示,约 5% 的 issue 通过多个 PR 解决,多数源于迭代式精化;multi-PR issue 的解决时间显著更长,中位解决时间是 single-PR issue 的 4 倍,commit 级活动也略高。研究为实践者提供规划与协调启示,并呼吁研究者建立考虑迭代解决模式的模型与工具,同时将分类体系扩展到 web 与移动应用等领域。
Video games are a special type of software that differ from other types of software systems in that they aim to deliver immersive experiences to users. As a result, issue reports (e.g., bug reports) in video game projects may require iterative fixes that span multiple pull requests (PRs). A PR is a mechanism used in platforms such as GitHub, which are built on distributed version control systems (e.g., Git), through which developers propose code changes for review, discussion, and eventual integration into the main codebase. We refer to an issue report that is linked to multiple PRs as a multi-PR issue. Despite their potential impact on development efforts and coordination, such multi-PR issues remain largely unexplored. In this paper, we present a large-scale empirical study of multi-PR issues in open-source game development. We analyze their prevalence, derive a taxonomy explaining why multiple PRs are associated with a single issue, and compare their resolution timelines and development effort against single-PR issues, i.e., issues resolved through exactly one PR. Our results show that approximately 5% of issues are resolved through multiple PRs. Most of these cases arise from iterative refinement. Quantitatively, multi-PR issues take substantially longer to resolve, with a median resolution time four times higher than that of single-PR issues. They are also associated with moderately higher commit-level activity. Our findings have practical implications for both practitioners and researchers. For practitioners, multi-PR issues require more careful planning, as they involve higher commit-level effort and are more likely to experience prolonged resolution times, potentially threatening release schedules. Moreover, when multiple contributors independently submit PRs for the same issue, teams risk duplicated implementation effort and increased review overhead, underscoring the importance of early coordination mechanisms (e.g., ownership assignment or consolidation of parallel fixes). For researchers, our results highlight the need for empirical models and tools that explicitly account for iterative resolution patterns rather than assuming single-PR fixes. We further encourage researchers to extend our taxonomy to other domains, such as web and mobile applications.