Automating Test-Suite Augmentation

Test suites are hardly ever created from scratch. Hence, automatic test case generation methods should take advantage of existing tests to produce high-quality test suites more efficiently. We present an approach for automatic test suite augmentation addressing this challenge. It modifies existing test cases in such a way that full branch coverage in specified target functions is achieved. It is based on symbolic execution and model checking, and has been implemented as an extension to FShell, a test case generation tool for C programs. Finally, we present a case study where we apply our tool to augment a model-based test suite for real industrial code of a Java Card applet firewall, ultimately achieving 100% branch coverage fully automatically.