Test automation, which involves the conversion of manual test cases to executable test scripts, is necessary to carry out efficient regression testing of GUI-based applications. However, test automation takes significant investment of time and skilled effort. Moreover, it is not a one-time investment: as the application or its environment evolves, test scripts demand continuous patching. Thus, it is challenging to perform test automation in a cost-effective manner. At IBM, we developed a tool, called ATA [1], [2], to meet this challenge. ATA has novel features that are designed to lower the cost of initial test automation significantly. Moreover, ATA has the ability to patch scripts automatically for certain types of application or environment changes. How well does ATA meet its objectives in the real world? In this paper, we present a detailed case study in the context of a challenging production environment: an enterprise web application that has over 6500 manual test cases, comes in two variants, evolves frequently, and needs to be tested on multiple browsers in time-constrained and resource-constrained regression cycles. We measured how well ATA improved the efficiency in initial automation. We also evaluated the effectiveness of ATA's change-resilience along multiple dimensions: application versions, browsers, and browser versions. Our study highlights several lessons for test-automation practitioners as well as open research problems in test automation.

As a test suite evolves, it can accumulate redundant tests. To address this problem, many test-suite reduction techniques, based on different measures of redundancy, have been developed. A more subtle problem, that can also cause test-suite bloat and that has not been addressed by existing research, is the accumulation of similar tests. Similar tests are not redundant by any measure; but, they contain many common actions that are executed repeatedly, which over a large test suite, can degrade execution time substantially.

Large software systems are developed by composing multiple programs. If the programs manipulate and exchange complex data, such as network packets or files, it is essential to establish that they follow compatible data formats. Most of the complexity of data formats is associated with the headers. In this paper, we address compatibility of programs operating over headers of network packets, files, images, etc. As format specifications are rarely available, we infer the format associated with headers by a program as a set of guarded layouts. In terms of these formats, we define and check compatibility of (a) producer-consumer programs and (b) different versions of producer (or consumer) programs. A compatible producer-consumer pair is free of type mismatches and logical incompatibilities such as the consumer rejecting valid outputs generated by the producer. A backward compatible producer (resp. consumer) is guaranteed to be compatible with consumers (resp. producers) that were compatible with its older version. With our prototype tool, we identified 5 known bugs and 1 potential bug in (a) sender-receiver modules of Linux network drivers of 3 vendors and (b) different versions of a TIFF image library.

In industrial practice, test cases often start out as steps described in natural language and are intended to be executed by a human. Since tests are executed repeatedly, they go through an automation process, in which they are converted to automated test scripts (or programs) that perform the test steps mechanically. Conventional test-automation techniques can be time-consuming, require specialized skills, and can produce fragile scripts. To address these limitations, we present a tool, called ata, for automating the test-automation task. Using a novel combination of natural-language processing, backtracking exploration, and learning, ata can significantly improve tester productivity in automating manual tests. ata also produces change-resilient scripts, which automatically adapt themselves in the presence of certain common types of user-interface changes.