Towards Practical and Useful Automated Program Repair for Debugging

Current automated program repair (APR) techniques are far from being practical and useful enough to be considered for realistic debugging. They rely on unrealistic assumptions including the requirement of a comprehensive suite of test cases as the correctness criterion and frequent program re-execution for patch validation; they are not fast; and their ability of repairing the commonly arising complex bugs by fixing multiple locations of the program is very limited. We hope to substantially improve APR's practicality, effectiveness, and usefulness to help people debug. Towards this goal, we envision PracAPR, an interactive repair system that works in an Integrated Development Environment (IDE) to provide effective repair suggestions for debugging. PracAPR does not require a test suite or program re-execution. It assumes that the developer uses an IDE debugger and the program has suspended at a location where a problem is observed. It interacts with the developer to obtain a problem specification. Based on the specification, it performs test-free, flow-analysis-based fault localization, patch generation that combines large language model-based local repair and tailored strategy-driven global repair, and program re-execution-free patch validation based on simulated trace comparison to suggest repairs. By having PracAPR, we hope to take a significant step towards making APR useful and an everyday part of debugging.