Dependency-Aware Web Test Generation

Web crawlers can perform long running in-depth explorations of a web application, achieving high coverage of the navigational structure. However, a crawling trace cannot be easily turned into a minimal test suite that achieves the same coverage. In fact, when the crawling trace is segmented into test cases, two problems arise: (1) test cases are dependent on each other, therefore they may raise errors when executed in isolation, and (2) test cases are redundant, since the same targets are covered multiple times by different test cases. In this paper, we propose DANTE, a novel web test generator that computes the test dependencies associated with the test cases obtained from a crawling session, and uses them to eliminate redundant tests and produce executable test schedules. DANTE can effectively turn a web crawler into a test case generator that produces minimal test suites, composed only of feasible tests that contribute to achieve the final coverage. Experimental results show that DANTE, on average, (1) reduces the error rate of the test cases obtained by crawling traces from 85% to zero, (2) produces minimized test suites that are 84% smaller than the initial ones, and (3) outperforms two competing crawling-based and model-based techniques in terms of coverage and breakage rate.