Ultra-Large Repair Search Space with Automatically Mined Templates: the Cardumen Mode of Astor

TL;DR

This paper introduces Cardumen, a new mode of the Astor repair library that uses mined templates to explore an ultra-large search space, significantly increasing the number of generated patches for real bugs.

Contribution

It presents the Cardumen repair approach with an unprecedented large search space, discovering numerous plausible patches and unique fixes not previously seen in program repair history.

Findings

8935 patches generated for 77 bugs in Defects4J

Largest number of synthesized patches reported

Identified 8 unique patches for bugs never previously repaired

Abstract

Astor is a program repair library which has different modes. In this paper, we present the Cardumen mode of Astor, a repair approach based mined templates that has an ultra-large search space. We evaluate the capacity of Cardumen to discover test-suite adequate patches (aka plausible patches) over the 356 real bugs from Defects4J. Cardumen finds 8935 patches over 77 bugs of Defects4J. This is the largest number of automatically synthesized patches ever reported, all patches being available in an open-science repository. Moreover, Cardumen identifies 8 unique patches, that are patches for Defects4J bugs that were never repaired in the whole history of program repair.