Fonte: Finding Bug Inducing Commits from Failures

• Main Authors: An, Gabin, Hong, Jingun, Kim, Naryeong, Yoo, Shin
• Format: Journal Article
• Language: English
• Published: 13-12-2022
• Subjects: Computer Science - Software Engineering
• DOI: 10.48550/arxiv.2212.06376

A Bug Inducing Commit (BIC) is a commit that introduces a software bug into
the codebase. Knowing the relevant BIC for a given bug can provide valuable
information for debugging as well as bug triaging. However, existing BIC
identification techniques are either too expensive (because they require the
failing tests to be executed against previous versions for bisection) or
inapplicable at the debugging time (because they require post hoc artefacts
such as bug reports or bug fixes). We propose Fonte, an efficient and accurate
BIC identification technique that only requires test coverage. Fonte combines
Fault Localisation (FL) with BIC identification and ranks commits based on the
suspiciousness of the code elements that they modified. Fonte reduces the
search space of BICs using failure coverage as well as a filter that detects
commits that are merely style changes. Our empirical evaluation using 130
real-world BICs shows that Fonte significantly outperforms state-of-the-art BIC
identification techniques based on Information Retrieval as well as neural code
embedding models, achieving at least 39% higher MRR. We also report that the
ranking scores produced by Fonte can be used to perform weighted bisection,
further reducing the cost of BIC identification. Finally, we apply Fonte to a
large-scale industry project with over 10M lines of code, and show that it can
rank the actual BIC within the top five commits for 87% of the studied real
batch-testing failures, and save the BIC inspection cost by 32% on average.