Refactoring-aware Block Tracking in Commit History

TL;DR

CodeTracker is a refactoring-aware tool that accurately tracks code block changes in commit history, outperforming existing AST diff tools in precision, recall, and speed, thereby aiding software maintenance and comprehension tasks.

Contribution

We introduce CodeTracker, a novel tool that improves accuracy and efficiency in tracking code block changes, addressing limitations of existing AST-based methods.

Findings

CodeTracker achieves 99.5% precision and recall.

It is faster than the baseline GumTree tool.

It effectively captures complete change histories of code blocks.

Abstract

Tracking statements in the commit history of a project is in many cases useful for supporting various software maintenance, comprehension, and evolution tasks. A high level of accuracy can facilitate the adoption of code tracking tools by developers and researchers. To this end, we propose CodeTracker, a refactoring-aware tool that can generate the commit change history for code blocks. To evaluate its accuracy, we created an oracle with the change history of 1,280 code blocks found within 200 methods from 20 popular open-source project repositories. Moreover, we created a baseline based on the current state-of-the-art Abstract Syntax Tree diff tool, namely GumTree 3.0, in order to compare the accuracy and execution time. Our experiments have shown that CodeTracker has a considerably higher precision/recall and faster execution time than the GumTree-based baseline, and can extract the complete change history of a code block with a precision and recall of 99.5% within 3.6 seconds on average.