Descriptive compound identifier names improve source code comprehension

In this paper, we analyze eye movement data of 26 participants using a quantitative and qualitative approach to investigate how people read natural language text in comparison to source code. In particular, we use the radial transition graph visualization to explore strategies of participants during these reading tasks and extract common patterns amongst participants. We illustrate via examples how visualization can play a role at uncovering behavior of people while reading natural language text versus source code. Our results show that the linear reading order of natural text is only partially applicable to source code reading. We found patterns representing a linear order and also patterns that represent reading of the source code in execution order. Participants also focus more on those areas that are important to comprehend core functionality and we found that they skip unimportant constructs such as brackets.

Nowadays, software development has been greatly influenced by question-answering communities, such as Stack Overflow. A new problem-solving paradigm has emerged, as developers post problems they encounter that are then answered by the community. In this paper, we propose a methodology that allows searching for solutions in Stack Overflow, using the main elements of a question post, including not only its title, tags, and body, but also its source code snippets. We describe a similarity scheme for these elements and demonstrate how structural information can be extracted from source code snippets and compared to further improve the retrieval of questions. The results of our evaluation indicate that our methodology is effective on recommending similar question posts allowing community members to search without fully forming a question.

Code search is an essential task in software development. Developers often search the internet and other code databases for necessary source code snippets to ease the development efforts. Code search techniques also help learn programming as novice programmers or students can quickly retrieve (hopefully good) examples already used in actual software projects. Given the recurrence of the code search activity in software development, there is an increasing interest in the research community. To improve the code search experience, the research community suggests many code search tools and techniques. These tools and techniques leverage several different ideas and claim a better code search performance. However, it is still challenging to illustrate a comprehensive view of the field considering that existing studies generally explore narrow and limited subsets of used components. This study aims to devise a grounded approach to understanding the procedure for code search and build an operational taxonomy capturing the critical facets of code search techniques. Additionally, we investigate evaluation methods, benchmarks, and datasets used in the field of code search.

Despite the extensive adoption of crowdsourcing for the timely, cost-effective, and high-quality completion of software development tasks, a large number of crowdsourced challenges are not able to acquire a winning solution, on time, and within the desired cost and quality thresholds. A possible reason for this is that we currently lack a systematic approach that would aid software managers during the process of designing software development tasks that will be crowdsourced. This paper attempts to extend the current knowledge on designing crowdsourced software development tasks, by empirically answering the following management questions: (a) what type of projects should be crowdsourced; (b) why should one crowdsource-in terms of acquired benefits; (c) where should one crowdsource-in terms of application domain; (d) when to crowdsource-referring to the time period of the year; (e) who will win or participate in the contest; and (f) how to crowdsource (define contest duration, prize, type of contest etc.) to acquire the maximum benefits-depending on the goal of crowdsourcing. To answer the aforementioned questions, we have performed a case study on 2,209 software development tasks crowdsourced through TopCoder platform. The results suggest that there are significant differences in the level to which crowdsourcing goals are reached, across different software development activities. Based on this observation we suggest that software managers should prioritize the goals of crowdsourcing, decide carefully upon the activity to be crowdsourced and then define the settings of the task.

In Engineering and Scientific computing, a significant number of software systems that are being commonly used by the Engineering community are developed and deployed as Open Source Systems (OSS). This collaborative development model has been widely accepted in both academia and industry. As these systems are typically developed by developers who are experts in their fields (e.g., Engineering), some of those programmers may be lacking an essential skillset today's software quality and engineering concepts (e.g., source code maintainability and analyzability, source code vulnerability, parallelization, etc.). An empirical study is presented that examines some of the source code quality aspects and programming practices (e.g., jumps statements, usage of recursion) from software engineering perspective in ten open source Engineering software systems. The studied systems are written in the C/C++ programming languages and comprised of over ten million lines of code, and present numerous tasks of the engineering community, including computer-aided design, computational fluid dynamics, and finite element analysis. Static analysis methods are applied to each system to determine the number of jump statements (Goto and Break statements) and functions that are recursively invoked. Functions that contain direct or indirect recursive calls are determined and counted. The results show that number of the used jump statements and functions that have recursive calls are significant and thus pose more of a roadblock to effectively and automatically maintain, comprehend, analyze, and re-engineer systems. Lastly, this leads to inefficiencies in a software engineer's ability to accomplish these common tasks. The study showed that issues in source code stemming from the lack of coding standards have increased over time and are prevalent.

Early prediction of quality of service using interface-level metrics, code-level metrics, and antipatterns

Software development is a collaborative process in which programmers build software by integrating all the stages of the software development life cycle (SDLC). A software repository is a central file storage location where various software packages are stored, and these packages are retrieved and shared between all the software development team members at various locations. The software repositories are divided into various categories based on cooperation, coordination, and communication among the stakeholders as well as evolutionary changes to various software arti-facts such as source code repositories, software bug repositories, historical repositories, run-time repositories and requirement documents, and other documentation. The software bug repository is an essential repository among the entire repositories since the completion of the software is entirely dependent on the bug fixing mechanism associated with this repository in software development. Today's software systems are larger and more complex as they go through various stages from the requirement 98analysis phase to the maintenance phase. A variety of tasks and activities are carried out in each stage of software development, and these are expensive and vulnerable to errors. During software development, a large number of software bugs are continuously generated, and that has become the main reason for the delay in software completion. Hence, there is a vast demand for computational intelligent techniques to accomplish various tasks of software development. In recent years, fuzzy logic techniques emerged and played an important role in various fields of data mining and text mining. Since most of the content related to software bug repositories is text in nature, it is possible to effectively use fuzzy logic techniques to analyze these software bugs.

Unlike text reading, the eye-movement behaviours associated with reading Python, a computer programming language, are largely understudied through a psycholinguistic lens. A general understanding of the eye movements involved in reading while troubleshooting Python, and how these behaviours compare to proofreading text, is critical for developing educational interventions and interactive tools for helping programmers debug their code. These data may also highlight to what extent humans use their underlying text reading ability when reading source code. The current work provides a profile of global reading behaviours associated with reading Python source code for debugging purposes. To this end, we recorded experienced programmers’ eye movements while they determined whether 21 different Python functions would produce the desired output, an incorrect output, or an error message. Some reading behaviours seem to mirror those found in text reading (e.g. effects of stimulus complexity), while others may be specific to reading code. Results suggest that semantic errors that produce undesired outputs in programming source code may influence early stages of processing, likely due to the largely top-down strategy employed by experienced programmers when reading source code. The findings are framed to invigorate discussion and further exploration into psycholinguistic analysis of human source code reading.

There exists a large body of work on the specification and detection of anti-patterns in the source code of software systems. However, there are very few studies on the origins of the occurrences of anti-patterns in the source code: do the very design of the systems lead to the occurrences of anti-patterns or are anti-patterns introduced during implementation? Knowing when anti-patterns are introduced could help software designers and developers improve the quality of the source code, for example by eliminating fault-prone anti-patterns early during the design of the systems, even before their implementation. Therefore, we detect occurrences of anti-patterns in design models and in the source code of some systems, trace these occurrences between design and implementation, and study their relation and impact on the source code. First, we analyze both the UML design models and the source code of 10 open-source systems and show that antipatterns exist in design models. We observe that, on average, 37% of the classes in the design models that belong to anti-patterns also exist in the source code and also play roles in the same anti-patterns. Second, we investigate two open-source systems to assess the impact of the anti-patterns in their design models on the source code in terms of changes and faults. We show that classes that have anti-patterns in the design models have more changes and faults in the source code. Our results suggest that the design of the systems lead to anti-patterns and that the antipatterns impact negatively the change-and fault-proneness of the classes in the source code. Thus, designers should be wary of anti-patterns in their design models and could benefit from tools that detect and trace these anti-patterns into the source code.

There are more and more developers as software is playing increasingly important roles in today’s economic and social development. As a result, evaluating developers’ expertise scientifically has become an urgent need for both Internet companies and developers. However, it seems that there is no satisfactory method to meet this demand currently. In this paper, we propose a solution to profile developers by analyzing their source code. We conduct the analysis of developers in terms of code quantity, code quality, skills, contribution, personalized commit time, and projects they participated in based on the GitLab code repositories. And we comprehensively evaluate developers’ expertise from four perspectives, which are code quantity, code quality, contribution and score of projects they participated in. Compared with existing methods, our evaluation indicators are more comprehensive. We design and implement an online tool that can provide developer searching and profiling. Our tool has been used in Neusoft and Wonders Group to characterize the expertise and performance of their software developers.

Maintaining traceability links of software systems is a crucial task for software management and development. Unfortunately, dealing with traceability links are typically taken as afterthought due to time pressure. Some studies attempt to use information retrieval-based methods to automate this task, but they only concentrate on calculating the textual similarity between various software artifacts and do not take into account the properties of such artifacts. In this paper, we propose a novel traceability link recovery approach, which comprehensively measures the similarity between use cases and source code by exploring their particular properties. To this end, we leverage and combine machine learning and logical reasoning techniques. On the one hand, our method extracts features by considering the semantics of the use cases and source code, and uses a classification algorithm to train the classifier. On the other hand, we utilize the relationships between artifacts and define a series of rules to recover traceability links. In particular, we not only leverage source code’s structural information, but also take into account the interrelationships between use cases. We have conducted a series of experiments on multiple datasets to evaluate our approach against existing approaches, the results of which show that our approach is substantially better than other methods.

A feature of the interpretive BASIC languages supplied on most microcomputers is that codes from several "BASICS" may be combined in the same program. When the executed code is correct and the code foreign to the interpreter being used is bypassed, problems do not occur. Thus, BASIC programs can be prepared which run on several different .machines. A front-end menu query is utilized to identify the brand of microcomputer on which the program is running. The source code (see Appendix) displays a hybrid BASIC program that has been used to transfer both text and BASIC programs among ffiM-PC, Radio Shack TRS80 Model ill, and Apple lIe microcomputers. Lines 240360 are consistent with the syntax rules for all three computers and present the menu through which the computer brand is identified. The user answers a query about whether to send or receive a file, and names the file to be accessed for transmission or the file to be received and stored. Lines 70-200 handle communications to and from the TRS-80 microcomputer, lines 370-610 control communications to and from the ffiM-PC, and lines 620-820 govern communications to and from the Apple lIe. If a machine other than one of the three listed is used, it may trap certain types of errors; that is, lines of code which will not run under the machine's interpreter may not be enterable from the keyboard. Should this situation arise, the user simply bypasses that line and continues to enter the remaining lines of program code. This is not a problem when the program executes because the unenterable lines would not have been executed on the machine. Communications from the sending to the receiving microcomputers are handled using standard asynchronous (RS-232)procedures. Our approach is to fit the microcomputers' serial communications ports with the appropriate vendor's RS-232 cables and then connect these cables using a modem eliminator. If the necessary cables are not readily available from the computer manufacturers, then substitutes as well as a modem eliminator may be purchased from a retail computer store or outlet. The demonstration program shown in the Appendix utilizes timing delays, set within the program, to mediate

Software Quality Assurance is a sub-process that ensures that developed software meets and complies with defined or standardized quality specifications. Focusing on source code, there are characteristics that can be used to evaluate the quality. Introductory courses must encourage freshmen students to improve internal quality of their source code, but only as sophomore they have contact with Software Engineering concepts, including Quality Assurance. In this paper we present a tool to source code quality evaluation aimed at supporting students to improve their source code and, consequently, their programming skills. The proposed tool uses quality reports (available to professional environment integrate with software repositories) to analyze students' source code and provide a feedback about the student coding. The proposed tool run locally, with few computational resources. In addition, we proposed the methodology to use the proposed tool: it consists of challenging students to perform a set of maintenance tasks in a controlled environment. We prepared a source code by introducing common defects, what decreases the quality of source code, and ask to students to perform maintenance tasks in order to both eliminate the introduced defects and introduce new features. After each modification, the students must evaluate their code using the proposed tool to obtain a feedback about quality of source code. To evaluate the approach and the tool, we created a survey and applied to students and the teacher. As a result, we show the benefits of using the proposed tool to both teachers and students perspectives. The results are positive to enhance the teaching-learning Software Quality Assurance to Software Engineering students.

One very important aspect of computer programming is reading source code. Even relatively small programs can consist of thousands of lines of code, and navigating through all this information can be time consuming and difficult. Whilst this can be considered a minor nuisance for sighted persons, for blind computer programmers the problem is more severe.The main aim of this research is to improve access to programming for any user unable or unwilling to use a visual system. The hypothesis is that providing a glance at the source code using a tailored, auditory overview will improve the reader's understanding of the program. It is hoped that these findings could also facilitate code reading and comprehension for all users.

Unit testing represents a key activity in software development and maintenance. Test suites with high internal quality facilitate maintenance activities, such as code comprehension and regression testing. Several guidelines have been proposed to help developers write good test suites. Unfortunately, such rules are not always followed resulting in the presence of bad test code smells (or simply test smells). Test smells have been defined as poorly designed tests and their presence may negatively affect the maintainability of test suites and production code. Despite the many studies that address code smells in general, until now there has been no empirical evidence regarding test smells (i) distribution in software systems nor (ii) their impact on the maintainability of software systems. This paper fills this gap by presenting two empirical studies. The first study is an exploratory analysis of 18 software systems (two industrial and 16 open source) aimed at analyzing the distribution of test smells in source code. The second study, a controlled experiment involving twenty master students, is aimed at analyzing whether the presence of test smells affects the comprehension of source code during software maintenance. The results show that (i) test smells are widely spread throughout the software systems studied and (ii) most of the test smells have a strong negative impact on the comprehensibility of test suites and production code.