FaCoY: a code-to-code search engine

Kisub Kim, Dongsun Kim, Tegawendé F. Bissyandé, Eunjong Choi, Li Li, Jacques Klein, Yves Le Traon

    Research output: Chapter in Book/Report/Conference proceedingConference PaperResearch

    86 Citations (Scopus)


    Code search is an unavoidable activity in software development. Various approaches and techniques have been explored in the literature to support code search tasks. Most of these approaches focus on serving user queries provided as natural language free-form input. However, there exists a wide range of use-case scenarios where a code-to-code approach would be most beneficial. For example, research directions in code transplantation, code diversity, patch recommendation can leverage a code-to-code search engine to find essential ingredients for their techniques. In this paper, we propose FaCoY, a novel approach for statically finding code fragments which may be semantically similar to user input code. FaCoY implements a query alternation strategy: instead of directly matching code query tokens with code in the search space, FaCoY first attempts to identify other tokens which may also be relevant in implementing the functional behavior of the input code. With various experiments, we show that (1) FaCoY is more effective than online code-to-code search engines; (2) FaCoY can detect more semantic code clones (i.e., Type-4) in BigCloneBench than the state-of-the-art; (3) FaCoY, while static, can detect code fragments which are indeed similar with respect to runtime execution behavior; and (4) FaCoY can be useful in code/patch recommendation.

    Original languageEnglish
    Title of host publicationProceedings
    Subtitle of host publication2018 ACM/IEEE 40th International Conference on Software Engineering - ICSE 2018
    EditorsMarsha Chechik, Mark Harman
    Place of PublicationNew York NY USA
    PublisherAssociation for Computing Machinery (ACM)
    Number of pages12
    ISBN (Print)9781450356381
    Publication statusPublished - 27 May 2018
    EventInternational Conference on Software Engineering 2018 - Gothenburg, Sweden
    Duration: 27 May 20183 Jun 2018
    Conference number: 40th
    https://ieeexplore.ieee.org/xpl/conhome/8452039/proceeding (Proceedings)


    ConferenceInternational Conference on Software Engineering 2018
    Abbreviated titleICSE 2018
    Internet address

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