Simplifying failure-inducing input
Ralf Hildebrandt, Andreas Zeller · 2000
Given some test case, a program fails. Which part of the test case is responsible for the particular failure? We show how our delta debugging algorithm generalizes and simplifies some failing input to a minimal test case that produces the failure. In a case study, the Mozilla web browser crashed after 95 user actions. Our prototype implementation automatically simplified the input to 3 relevant user actions. Likewise, it simplified 896 lines of HTML to the single line that caused the failure. The case study required 139 automated test runs, or 35 minutes on a 500 MHz PC. Categories and Subject Descriptors D.2.5 [Software Engineering]: Testing and Debugging---debug- ging aids, diagnostics, testing tools, tracing General Terms Automated debugging, combinatorial testing 1. INTRODUCTION Often people who encounter a bug spend a lot of time investigating which changes to the input file will make the bug go away and which changes will not affect it. --- Richard Stallman, Using and Port...