Both complexity of code change for bug fixing and bug severity play an important role in release planning when considering which bugs should be fixed in a specific release under certain constraints. This work investigates whether there are significant differences between bugs of different severity levels regarding the complexity of code change for fixing the bugs. Code change complexity is measured by the number of modified lines of code, source files, and packages, as well as the entropy of code change. We performed a case study on 20 Apache open source software (OSS) projects using commit records and bug reports. The study results show that (1) for bugs of high severity levels (i.e. Blocker, Critical and Major in JIRA), there is no significant difference on the complexity of code change for fixing bugs of different severity levels for most projects, while (2) for bugs of low severity levels (i.e. Major, Minor and Trivial in JIRA), fixing bugs of a higher severity level needs significantly more complex code change than fixing bugs of a lower severity level for most projects. These findings provide useful and practical insights for effort estimation and release planning of OSS development.

中文翻译：

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Bug 严重性是否与 Bug 修复更改复杂性一致？

在考虑在特定约束下应该在特定版本中修复哪些错误时，用于修复错误的代码更改的复杂性和错误严重性在发布计划中都起着重要作用。这项工作调查了不同严重级别的错误在修复错误的代码更改复杂性方面是否存在显着差异。代码更改复杂度通过修改的代码行数、源文件和包的数量以及代码更改的熵来衡量。我们使用提交记录和错误报告对 20 个 Apache 开源软件 (OSS) 项目进行了案例研究。研究结果表明（1）对于高严重级别的错误（即JIRA中的Blocker，Critical和Major），大多数项目修复不同严重级别的 bug 的代码更改复杂度没有显着差异，而（2）对于低严重级别的 bug（即 JIRA 中的 Major、Minor 和 Trivial），修复更高级别的 bug对于大多数项目，需要比修复严重程度较低的错误更复杂的代码更改。这些发现为 OSS 开发的工作量估计和发布计划提供了有用且实用的见解。