Merge Nature: a tool to support research about merge conflicts
The modern software development model requires concurrent programming to create more complex programs. As such, existing approaches are able to track and merge the changes made on a code repository, allowing more developers to work collaboratively. Despite these solutions, 10% to 20% of all merges result in conflicts, such as when changes are made on the same file region. Existing studies have analyzed, prevented, predicted, and even automatically resolved merge conflicts. However, they are usually focused on a specific language or on language-independent information from the source-code lines involved in the conflict. This situation hinders the generalization of results. To enrich the information to be used by further studies about merges, we present the Merge Nature Tool, which recreates all project merges and extracts characteristics from conflicts, such as the resolutions adopted by developers, and the language constructs involved in the conflict for Java, C++, and Python files. The tool was evaluated regarding reproducibility and generalization. It was able to reproduce 87.75% of the results of a previous study. The differences can be explained by newly introduced features. On the other hand, regarding generalization, the tool was used to analyze a set of 100 merges from Python projects. The merges were analyzed manually to ensure the reliability of the results. We found that 100% of the data matched the expected result. We expect this tool to facilitate future work regarding merge conflicts. For instance, it may allow comparing the characteristics of merge conflicts from different programming languages.
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