Software testing is a critical activity to ensure that software complies with its specification. However, current software testing activities tend not to be completely effective when applied in specific software domains in Virtual Reality (VR) that has several new types of features such as images, sounds, videos, and differentiated interaction, which can become sources of new kinds of faults. This paper presents an overview of the main VR characteristics that can have an impact on verification, validation, and testing (VV&T). Furthermore, it analyzes some of the most successful VR open-source projects to draw a picture concerning the danger of the lack of software testing activities. We compared the current state of software testing practice in open-source VR projects and evaluate how the lack of testing can be damaging to the development of a product. We assessed the incidence of code smells and verified how such projects behave concerning the tendency to present faults. The results showed that the practice of software testing is not yet widespread in the development of VR applications. It was also found that there is a high incidence of code smells in VR projects. Regarding fault-proneness the results showed that about 12.2% of the classes analyzed in VR projects are fault-prone. Regarding the application of software testing techniques on VR projects, it was observed that only a small number of projects are concerned about developing test cases for VR projects, perhaps because we still do not have the necessary tools to help in this direction. Concerning smells, we concluded that there is a high incidence in VR projects, especially regarding implementing smells and this high incidence can have a significant influence on faults. Finally, the study related to fault proneness pointed out that the lack of software testing activity is a significant risk to the success of the projects.

中文翻译：

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迈向虚拟现实程序的系统测试（扩展版）

软件测试是确保软件符合其规范的关键活动。然而，当前的软件测试活动在应用于虚拟现实 (VR) 中的特定软件领域时往往并不完全有效，虚拟现实 (VR) 具有几种新类型的功能，例如图像、声音、视频和差异化交互，这些功能可以成为新类型的来源的故障。本文概述了可能对验证、确认和测试 (VV&T) 产生影响的主要 VR 特性。此外，它分析了一些最成功的 VR 开源项目，以描绘缺乏软件测试活动的危险。我们比较了开源 VR 项目中软件测试实践的当前状态，并评估了缺乏测试如何对产品开发造成损害。我们评估了代码异味的发生率，并验证了此类项目在出现错误的趋势方面的表现。结果表明，软件测试的实践在VR应用程序的开发中尚未普及。还发现 VR 项目中代码异味的发生率很高。关于故障倾向性，结果表明在 VR 项目中分析的类中约有 12.2% 是容易发生故障的。关于软件测试技术在 VR 项目中的应用，观察到只有少数项目关注为 VR 项目开发测试用例，也许是因为我们仍然没有必要的工具来帮助实现这个方向。关于气味，我们得出结论，VR 项目的发生率很高，尤其是在实施气味方面，这种高发生率会对故障产生重大影响。最后，与故障倾向相关的研究指出，缺乏软件测试活动是项目成功的重大风险。