  Datasets such as Defects4J and BugsInPy that contain bugs from real-world
software projects are necessary for a realistic evaluation of automated
debugging tools. However these datasets largely identify only a single bug in
each entry, while real-world software projects (including those used in
Defects4J and BugsInPy) typically contain multiple bugs at the same time. We
lift this limitation and describe an extension to these datasets in which
multiple bugs are identified in individual entries. We use test case
transplantation and fault location translation, in order to expose and locate
the bugs, respectively. We thus provide datasets of true multi-fault versions
within real-world software projects, which maintain the properties and
usability of the original datasets.
