软工学者Ming Wen及其顶会论文解读

前言

本文旨在介绍软工学者Ming Wen及其今年ICSE 2018顶会论文“Context-Aware Patch Generation for Better Automated Program Repair”。

一、论文及作者信息

论文名称：Context-Aware Patch Generation for Better Automated Program Repair
作者：Ming Wen（一作），Shing-Chi Cheung（五作，导师）
单位： The Hong Kong University of Science and Technology [2]
香港科技大学（The Hong Kong University of Science and Technology），简称港科大（HKUST），为东亚研究型大学协会、环太平洋大学联盟、亚洲大学联盟、中国大学校长联谊会、京港大学联盟重要成员，并获AACSB和EQUIS双重认证，是一所亚洲顶尖、国际知名的研究型大学。该校以科技和商业管理为主、人文及社会科学并重，尤以商科和工科见长。

建校二十多年来，港科大创造了全球最细单壁纳米碳管、全球最高像素的照片、全球首创的智能杀菌涂层、全球排名第一的EMBA课程等国际领先的教研成果，培养了大疆创新创始人汪滔、民建联主席李慧琼、腾讯集团首席财务官罗硕瀚等各领域杰出人才。[1]

他们实验室还有一篇文章应该关注一下：
ChangeLocator: Locate Crash-Inducing Changes Based on Crash Reports
Rongxin Wu, Ming Wen, Shing-Chi Cheung, Hongyu Zhang
ICSE 2018 Journal first papers

Ming Wen（文明）的个人主页：http://home.cse.ust.hk/~mwenaa/
联系方式：mwenaa@cse.ust.hk

文明

他发表的文章：

Publications
[ESEC/FSE’18] Ying Wang, Ming Wen, Zhenwei Liu, Rongxin Wu, Rui Wang, Bo Yang, Hai Yu, Zhiliang Zhu and Shing-Chi Cheung. Do the Dependency Conflicts in My Project Matter? In The ACM Joint European Software Engineering Conference and Symposium on the Foundations of Software Engineering, Technical Research Paper, Lake Buena Vista, Florida, 4 Nov - 9 Nov 2018, To Appear. (Acceptance ratio 18.6%=55/295)
[ICSE’18] Ming Wen, Junjie Chen, Rongxin Wu, Dan Hao and Shing-Chi Cheung. Context-Aware Patch Generation for Better Automated Program Repair. In International Conference on Software Engineering, Technical Research Paper, Gothenburg, Sweden, May 27 - 3 June 2018. (Acceptance ratio 20.9%=105/502)
[EmSE’17] Rongxin Wu, Ming Wen, Shing-Chi Cheung, and Hongyu Zhang. ChangeLocator: Locate Crash-Inducing Changes Based on Crash Reports. In Empirical Software Engineering, 2017
[ASE’16] Ming Wen, Rongxin Wu and Shing-Chi Cheung. Locus: Locating Bugs from Software Changes. In Proceedings of the 31st IEEE/ACM International Conference on Automated Software Engineering, Technical Research Paper, Singapore, 3 Sep - 7 Sep, 2016, 262-273. (Acceptance ratio 19.1%=57/298) [Slides][Dataset][Prototype]
[SANER’14] Xin Xia, David Lo, Ming Wen, Emad Shihab and Bo Zhou. An Empirical Study of Bug Report Field Reassignment. Joint Meeting of the 18th European Conference on Software Maintenance and Reengineering and the 21st Working Conference on Reverse Engineering. IEEE, 2014: 174-183.

这个也太强了吧。基本上都是最好的文章。

这些工作还和Xin Xia, David Lo有关，真的可以好好看看。

个人简介：

I am currently a PhD candidate in the third year from the department of Computer Science and Engineering of the Hong Kong University of Science and Technology. It’s my honour to be supervised by Prof. Shing-Chi CHEUNG. My research interests are mainly in program analysis, mining software changes and defect prediction. Before joining HKUST, I received my Bachelor Degree of Engineering in June 2014 from the Colloge of Computer Science and Technology of Zhejiang University.

2014年从浙大毕业，现在是博士三年级，估计是硕博连读。
16年，也就是博士第二年，就发了一篇顶会，太厉害啦。
同时还是浙大的优秀毕业生，算是前途无量了。

（我觉得这些优秀的人成功确实有原因，人家比你优秀，还比你努力，这就是正循环。正所谓不进则退，竞争确实激烈。）

二、论文内容

The eﬀectiveness of search-based automated program repair is limited in the number of correct patches that can be successfully generated. There are two causes of such limitation. First, the search space does not contain the correct patch. Second, the search space is huge and therefore the correct patch cannot be generated (i.e., correct patches are either generated after incorrect plausible ones or not generated within the time budget).

这个是重点啊。对search space讲的非常详细，很久没看到将search space的文章了

论文的动机：

To increase the likelihood of including the correct patches in the search space, we propose to work at a fine granularity in terms of AST nodes. This, however, will further enlarge the search space, increasing the challenge to fnd the correct patches. We address the challenge by devising a strategy to prioritize the candidate patches based on their likelihood of being correct. Specifcally, we study the use of AST nodes’ context information to estimate the likelihood.

作者要在AST node这个粒度上做修复，然而AST 粒度会增大search space，提高找到正确补丁的难度会大大增加。
作者恰恰还解决了这个问题，这还是很酷的。他们设计了一个策略（基于他们是正确补丁的可能性）对这些候选补丁进行排序。利用上下文信息来估算。

作者的工作：

In this paper, we propose CapGen, a context-aware patch generation technique. The novelty which allows CapGen to produce more correct patches lies in three aspects: (1) The fne-granularity design enables it to fnd more correct fxing ingredients; (2) The context-aware prioritization of mutation operators enables it to constrain the search space; (3) Three context-aware models enable it to rank correct patches at high positions before incorrect plausible ones. We evaluate CapGen on Defects4J and compare it with the state-of-the-art program repair techniques. Our evaluation shows that CapGen outperforms and complements existing techniques. CapGen achieves a high precision of 84.00% and can prioritize the correct patches before 98.78% of the incorrect plausible ones.

这个工作感觉很实，具体亮点在于：1）有工具，2）粒度在AST上，3）用了上下文信息来排序，计算可能性（类似于fitness function），4）自己建立了三个context-aware模型。
此外，还做了一个evaluation。工作量确实够了。

三、论文特色

1）看看人家写的Abstract

CapGen achieves a high precision of 84.00% and can prioritize the correct patches before 98.78% of the incorrect plausible ones.
感觉就很酷，有数据支撑，很明了。

2）开头找的这个背景资料也比较罕见，感觉是做了工作的，反正我是找不到这个文献的，很酷。

A recent study shows that the global cost of general debugging is 312 billion dollars annually and software developers spend 50% of their time on fxing bugs [6].
[6] Tom Britton, Lisa Jeng, Graham Carver, Paul Cheak, and Tomer Katzenellenbogen. 2013. Reversible debugging software. Judge Bus. School, Univ. Cambridge,
Cambridge, UK, Tech. Rep (2013).

四、生词收集

devise
VERB 设计;发明;策划;想出
If you devise a plan, system, or machine, you have the idea for it and design it.

prioritize
英 [praɪˈɒrətaɪz] 美 [praɪˈɔ:rətaɪz]
vt. 优先处理;按重要性排列，划分优先顺序
按重要性排列；划分优先顺序 to put tasks, problems, etc. in order of importance, so that you can deal with the most important first
[VN] 优先处理 to treat sth as being more important than other things

五、好句摘录

We address the challenge by devising a strategy to prioritize the candidate patches based on their likelihood of being correct.
注意devise，还有address the challenge

参考文献

[1] 香港科技大学. https://baike.baidu.com/item/香港科技大学/1670844?fromtitle=The%20Hong%20Kong%20University%20of%20Science%20and%20Technology&fromid=11210929&fr=aladdin
[2] https://2018.msrconf.org/profile/mingwen

文末诗词

桐花半亩，静锁一庭愁雨。洒空阶、夜阑未休，故人剪烛西窗语。似楚江暝宿，风灯零乱，少年羁旅。
——周邦彦《锁窗寒》

大有一种相思少年羁旅之忧愁。