Abstract

Nowadays, developing software would be unthinkable without the use of third-party packages. Although such code reuse helps to achieve rapid continuous delivery of software to end-users, blindly reusing code has its pitfalls. Prior work investigated the rationale for using packages of small size, known as trivial packages, that implement simple functionality. This prior work showed that, although these trivial packages are simple, they are popular and prevalent in the \npm ecosystem. This popularity and prevalence of trivial packages piqued our interest in questioning; first, the `triviality' of these packages and, second, the impact of using these packages on the quality of the client software applications.


To better understand the `triviality' of trivial packages and their impact, in this thesis we report on two large scale empirical studies. In both studies, we mine a large set of JavaScript applications that use trivial \npm packages. In the first study, we evaluate the `triviality' of these packages from two complementary points of view: based on application usage and ecosystem usage. Our result shows that trivial packages are being used in important JavaScript files, by the means of their `centrality', in software applications. Additionally, by analyzing all external package API calls in these JavaScript files, we find that a high percentage of these API calls are attributed to trivial packages. Therefore, these packages play a significant role in JavaScript files. Furthermore, in the package dependency network, we observe that 16.8% packages are trivial and in some cases removing a trivial package can break approximately 30% of the packages in the ecosystem. In the second study, we started by understanding the circumstances which incorporate trivial packages in software applications. We analyze and classify commits that introduce trivial packages into software applications. We notice that developers resort to trivial packages while performing a wild range of development tasks that are mostly related to `Building' and `Refactoring'. We empirically evaluate the bugginess of the files and applications that use trivial packages. Our result shows that JavaScript files and applications that use trivial packages tend to have a higher percentage of bug-fixing commits than files and applications that do not depend on trivial packages.
Overall, the findings of our thesis indicate that although smaller in size and complexity, trivial packages are highly depended on packages. These packages may be trivial by the means of size, their utility in software applications suggests that their role is not so trivial.