Utilizing output in Web application server-side testing

This thesis investigates the utilization of web application output in enhancing automated server-side code testing. The server-side code is the main driving force of a web application generating client-side code, maintaining the state and communicating with back-end resources. The output observed in those elements provides a valuable resource that can potentially enhance the efficiency and effectiveness of automated testing. The thesis aims to explore the use of this output in test data generation, test sequence regeneration, augmentation and test case selection. This thesis also addresses the web-specific challenges faced when applying search based test data generation algorithms to web applications and dataflow analysis of state variables to test sequence regeneration. The thesis presents three tools and four empirical studies to implement and evaluate the proposed approaches: SWAT (Search based Web Application Tester) is a first application of search based test data generation algorithms for web applications. It uses values dynamically mined from the intermediate and the client-side output to enhance the search based algorithm. SART (State Aware Regeneration Tool) uses dataflow analysis of state variables, session state and database tables, and their values to regenerate new sequences from existing sequences. SWAT-U (SWAT-Uniqueness) augments test suites with test cases that produce outputs not observed in the original test suite’s output. Finally, the thesis presents an empirical study of the correlation between new output based test selection criteria and fault detection and structural coverage. The results confirm that using the output does indeed enhance the effectiveness and efficiency of search based test data generation and enhances test suites’ effectiveness for test sequence regeneration and augmentation. The results also report that output uniqueness criteria are strongly correlated with both fault detection and structural coverage and are complementary to structural coverage.