Code Smells and Refactoring: A Tertiary Systematic Review of Challenges and Observations
This work addresses the gap between code smells and refactoring for software engineering researchers and practitioners, but it is incremental as it synthesizes existing literature without introducing new methods or data.
The paper conducted a tertiary systematic review to identify known observations and unresolved challenges in code smells and refactoring, revealing their strong relationship with quality attributes like maintainability and testability, and identifying 13 open issues for future research.
In this paper, we present a tertiary systematic literature review of previous surveys, secondary systematic literature reviews, and systematic mappings. We identify the main observations (what we know) and challenges (what we do not know) on code smells and refactoring. We show that code smells and refactoring have a strong relationship with quality attributes, i.e., with understandability, maintainability, testability, complexity, functionality, and reusability. We argue that code smells and refactoring could be considered as the two faces of a same coin. Besides, we identify how refactoring affects quality attributes, more than code smells. We also discuss the implications of this work for practitioners, researchers, and instructors. We identify 13 open issues that could guide future research work. Thus, we want to highlight the gap between code smells and refactoring in the current state of software-engineering research. We wish that this work could help the software-engineering research community in collaborating on future work on code smells and refactoring.