Equivalent Mutants in the Wild: Identifying and Efficiently Suppressing Equivalent Mutants for Java Programs
The presence of equivalent mutants has long been considered a major obstacle to the widespread adoption of mutation analysis and mutation testing. This paper presents a study on the types and prevalence of equivalent mutants in real-world Java programs. We conducted a ground-truth analysis of 1,992 mutants, sampled from 7 open source Java projects. Our analysis identified 215 equivalent mutants, which we grouped based on two criteria that describe why the mutants are equivalent and how challenging their detection is. From this analysis, we observed that (1) the median equivalent mutant rate across the 7 projects is 2.97%; (2) many equivalent mutants are caused by common programming patterns and their detection is not much more complex than structural pattern matching over an abstract syntax tree.
Based on the findings of our ground-truth analysis, we developed Equivalent Mutant Suppression (EMS), a technique that comprises 10 efficient and targeted analyses. We evaluated EMS on 19 open- source Java projects, comparing the effectiveness and efficiency of EMS to two variants of Trivial Compiler Equivalence (TCE), the current state of the art in equivalent mutant detection. Additionally, we analyzed all 9,047 equivalent mutants reported by any tool to better understand the types and frequencies of equivalent mutants found. Overall, EMS detects 8,776 equivalent mutants within 325 seconds; TCE detects 2,124 equivalent mutants in 2,938 hours.
Wed 18 SepDisplayed time zone: Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna change
10:30 - 11:50 | Code Mutation and ReductionTechnical Papers at EI 10 Fritz Paschke Chair(s): Andreas Zeller CISPA Helmholtz Center for Information Security | ||
10:30 20mTalk | Large Language Models for Equivalent Mutant Detection: How Far Are We?ACM SIGSOFT Distinguished Paper Award Technical Papers Zhao Tian Tianjin University, Honglin Shu Kyushu University, Dong Wang Tianjin University, Xuejie Cao Tianjin University, Yasutaka Kamei Kyushu University, Junjie Chen Tianjin University DOI Pre-print | ||
10:50 20mTalk | An Empirical Examination of Fuzzer Mutator Performance Technical Papers James Kukucka George Mason University, Luís Pina University of Illinois at Chicago, Paul Ammann George Mason University, Jonathan Bell Northeastern University DOI | ||
11:10 20mTalk | Equivalent Mutants in the Wild: Identifying and Efficiently Suppressing Equivalent Mutants for Java Programs Technical Papers Benjamin Kushigian University of Washington, Samuel Kaufman University of Washington, Ryan Featherman University of Washington, Hannah Potter University of Washington, Ardi Madadi University of Washington, René Just University of Washington DOI | ||
11:30 20mTalk | LPR: Large Language Models-Aided Program Reduction Technical Papers Mengxiao Zhang University of Waterloo, Yongqiang Tian Hong Kong University of Science and Technology, Zhenyang Xu University of Waterloo, Yiwen Dong University of Waterloo, Shin Hwei Tan Concordia University, Chengnian Sun University of Waterloo DOI | ||