skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Subtle Bugs Everywhere: Generating Documentation for Data Wrangling Code
Data scientists reportedly spend 60 to 80 percent of their time in their daily routines on data wrangling, i.e. cleaning data and extracting features. However, data wrangling code is often repetitive and error-prone to write. Moreover, it is easy to introduce subtle bugs when reusing and adopting existing code, which result not in crashes but reduce model quality. To support data scientists with data wrangling, we present a technique to generate interactive documentation for data wrangling code. We use (1) program synthesis techniques to automatically summarize data transformations and (2) test case selection techniques to purposefully select representative examples from the data based on execution information collected with tailored dynamic program analysis. We demonstrate that a JupyterLab extension with our technique can provide documentation for many cells in popular notebooks and find in a user study that users with our plugin are faster and more effective at finding realistic bugs in data wrangling code.  more » « less
Award ID(s):
1852260
PAR ID:
10313199
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proceedings of the 36th IEEE/ACM International Conference on Automated Software Engineering (ASE), Los Alamitos, CA: IEEE Computer Society
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Static analysis tools have demonstrated effectiveness at finding bugs in real world code. Such tools are increasingly widely adopted to improve software quality in practice. Automated Program Repair (APR) has the potential to further cut down on the cost of improving software quality. However, there is a disconnect between these effective bug-finding tools and APR. Recent advances in APR rely on test cases, making them inapplicable to newly discovered bugs or bugs difficult to test for deterministically (like memory leaks). Additionally, the quality of patches generated to satisfy a test suite is a key challenge. We address these challenges by adapting advances in practical static analysis and verification techniques to enable a new technique that finds and then accurately fixes real bugs without test cases. We present a new automated program repair technique using Separation Logic. At a high-level, our technique reasons over semantic effects of existing program fragments to fix faults related to general pointer safety properties: resource leaks, memory leaks, and null dereferences. The procedure automatically translates identified fragments into source-level patches, and verifies patch correctness with respect to reported faults. In this work we conduct the largest study of automatically fixing undiscovered bugs in real-world code to date. We demonstrate our approach by correctly fixing 55 bugs, including 11 previously undiscovered bugs, in 11 real-world projects. 
    more » « less
  2. Coverage-based fault localization has been extensively studied in the literature due to its effectiveness and lightweightness for real-world systems. However, existing techniques often utilize coverage in an oversimplified way by abstracting detailed coverage into numbers of tests or boolean vectors, thus limiting their effectiveness in practice. In this work, we present a novel coverage-based fault localization technique, Grace, which fully utilizes detailed coverage information with graph-based representation learning. Our intuition is that coverage can be regarded as connective relationships between tests and program entities, which can be inherently and integrally represented by a graph structure: with tests and program entities as nodes, while with coverage and code structures as edges. Therefore, we first propose a novel graph-based representation to reserve all detailed coverage information and fine-grained code structures into one graph. Then we leverage Gated Graph Neural Network to learn valuable features from the graph-based coverage representation and rank program entities in a listwise way. Our evaluation on the widely used benchmark Defects4J (V1.2.0) shows that Grace significantly outperforms state-of-the-art coverage-based fault localization: Grace localizes 195 bugs within Top-1 whereas the best compared technique can at most localize 166 bugs within Top-1. We further investigate the impact of each Grace component and find that they all positively contribute to Grace. In addition, our results also demonstrate that Grace has learnt essential features from coverage, which are complementary to various information used in existing learning-based fault localization. Finally, we evaluate Grace in the cross-project prediction scenario on extra 226 bugs from Defects4J (V2.0.0), and find that Grace consistently outperforms state-of-the-art coverage-based techniques. 
    more » « less
  3. This paper presents a novel end-to-end approach to program repair based on sequence-to-sequence learning. We devise, implement, and evaluate a technique, called SEQUENCER, for fixing bugs based on sequence-to-sequence learning on source code. This approach uses the copy mechanism to overcome the unlimited vocabulary problem that occurs with big code. Our system is data-driven; we train it on 35,578 samples, carefully curated from commits to open-source repositories. We evaluate SEQUENCER on 4,711 independent real bug fixes, as well on the Defects4J benchmark used in program repair research. SEQUENCER is able to perfectly predict the fixed line for 950/4,711 testing samples, and find correct patches for 14 bugs in Defects4J benchmark. SEQUENCER captures a wide range of repair operators without any domain-specific top-down design. 
    more » « less
  4. Automated Program Repair (APR) is one of the most recent advances in automated debugging, and can directly fix buggy programs with minimal human intervention. Although various advanced APR techniques (including search-based or semantic-based ones) have been proposed, they mainly work at the source-code level and it is not clear how bytecode-level APR performs in practice. Also, empirical studies of the existing techniques on bugs beyond what has been reported in the original papers are rather limited. In this paper, we implement the first practical bytecode-level APR technique, PraPR, and present the first extensive study on fixing real-world bugs (e.g., Defects4J bugs) using JVM bytecode mutation. The experimental results show that surprisingly even PraPR with only the basic traditional mutators can produce genuine fixes for 17 bugs; with simple additional commonly used APR mutators, PraPR is able to produce genuine fixes for 43 bugs, significantly outperforming state-of-the-art APR, while being over 10X faster. Furthermore, we performed an extensive study of PraPR and other recent APR tools on a large number of additional real-world bugs, and demonstrated the overfitting problem of recent advanced APR tools for the first time. Lastly, PraPR has also successfully fixed bugs for other JVM languages (e.g., for the popular Kotlin language), indicating PraPR can greatly complement existing source-code-level APR. 
    more » « less
  5. We present LeJit, a template-based framework for testing Java just-in-time (JIT) compilers. Like recent template-based frameworks, LeJit executes a template---a program with holes to be filled---to generate concrete programs given as inputs to Java JIT compilers. LeJit automatically generates template programs from existing Java code by converting expressions to holes, as well as generating necessary glue code (i.e., code that generates instances of non-primitive types) to make generated templates executable. We have successfully used LeJit to test a range of popular Java JIT compilers, revealing five bugs in HotSpot, nine bugs in OpenJ9, and one bug in GraalVM. All of these bugs have been confirmed by Oracle and IBM developers, and 11 of these bugs were previously unknown, including two CVEs (Common Vulnerabilities and Exposures). Our comparison with several existing approaches shows that LeJit is complementary to them and is a powerful technique for ensuring Java JIT compiler correctness. 
    more » « less