A framework for studying and predicting bug propagation through code cloning for mobile apps

代码克隆（例如，复制/粘贴）是一种常见但有争议的软件工程实践，程序员在开发和维护期间经常使用它来重复公共功能。这种做法导致代码库中存在相同或几乎相似的代码片段，也称为代码克隆。两个彼此相似的代码片段形成一个克隆对。虽然许多研究已经确定了代码克隆的一些积极影响，但其他研究也显示了强有力的负面影响的经验证据。代码克隆可能与代码库中的错误和不一致直接相关。如果代码库中的特定代码片段包含临时隐藏的错误，并且程序员将该代码片段复制到其他几个地方而不知道该错误的存在，则原始代码片段中的错误将被传播。既然软件bug是任何软件的主要关注点，那么就必须有工具和框架来处理软件bug。然而，没有研究在代码克隆期间错误传播发生的频率。如果不研究bug传播的强度，我们就不能很好地认识到代码克隆对软件进化和维护的影响。此外，还没有研究调查移动应用程序的代码克隆的传播错误。考虑到Push interactive主要开发手机应用，所以确保他们的软件应用不存在这些普遍存在的漏洞是很重要的。然而，到目前为止，他们还没有任何这样的框架来研究通过代码克隆（通过复制/粘贴现有的有bug的代码片段来传播bug）来传播bug。此外，重要的是要有一个预测模型，以便该模型可以预测哪些克隆片段在未来的进化过程中可能会遇到这种传播错误。有了这样的工具集，Push Interactions就能够清楚地了解手机应用中是否存在代码克隆，它们与漏洞的关系，发现哪些克隆可能与漏洞有关，并预测哪些克隆存在漏洞。这将确保适当的维护和发展他们的移动软件应用程序。

Code cloning (i.e., copy/pasting) is a common yet controversial software engineering practice, which is often practised by the programmers during development and maintenance for repeating common functionalities. Such a practice results the existence of identical or nearly similar code fragments, also known as code clones, in a code-base. Two code fragments that are similar to each other form a clone-pair. While a number of studies have identified some positive impacts of code clones, other studies have shown strong empirical evidence of negative impacts too. Code clones can be directly related to bugs and inconsistencies in the code-base. If a particular code fragment in a code-base contains a temporarily hidden bug, and a programmer copies that fragment to several other places being unaware of the presence of the bug, the bug in the original fragment gets propagated. Given that software bugs are of primary concerns of any software, one must need to have tools and frameworks to deal with software bugs. However, there is no study on how frequently bug-propagation occurs during code cloning. Without studying the intensity of bug-propagation we cannot properly realize the impacts of code clones on software evolution and maintenance. Furthermore, there are no studies that investigated the propagated bugs for code clones for mobile applications. Given that Push Interactions mainly develop mobile applications, it is important for Push to make sure that their software applications do not have many of these propagated bugs. However, until now they do not have any such frameworks that can study the bug propagation through code cloning (propagation of bugs through copy/pasting of existing buggy code fragments). Furthermore, it is important to have a prediction model so that the model could predict which clone fragments might experience such propagated bugs in future during the evolution. With such toolset, Push Interactions would be able to have a clear idea about the presence of code clones in their mobile applications, their relationships to bugs, will find which clones are likely involve with bugs, and can predict the buggy clones. These will ensure proper maintenance and evolution of their mobile software applications.