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Thomas Arts
Professor and co-founder of QuviQ AB
QuviQ AB

Prof Thomas Arts is the co-founder and CTO of Quviq, a small company that produced QuickCheck, as testing tool for Erlang. Thomas has over 30 publications in various journals and has experience refereeing conferences and workshops. He has successfully introduced some new technologies to the industry, the latest being QuickCheck, a tool for property based testing and aims to support test driven development. Thomas is also a professor at Chalmers University of Technology in Gothenburg, Sweden.

Thomas was one of the members of Ericsson's computer science lab where he worked on program verification and the development of the Erlang programming language. He has also worked in the broad spectrum theoretical computer science, formal methods and industrial case-study research, mainly applying all kind of techniques to systems written in Erlang. 

Thomas Arts is Giving the Following Talks
Tutorial: Using QuickCheck for testing stateful systems

Testing is a major part of all software development—yet no matter how much effort is spent on it, some errors always seem to slip through. Cases which no‐one thought to test crash systems late in development or out in the field, revealing errors which cost time and money to analyze, diagnose, and fix. In the worst case, such errors reveal fundamental flaws which force a redesign of part of the system, at disproportionate cost. 

The Quviq QuickCheck automated testing tool addresses these problems by generating test cases from a concise specification (so that many more cases can be tested), and simplifying failing cases to a minimal example on a test failure (so that fault diagnosis is quick and easy). QuickCheck enables developers to dramatically improve test coverage, and find obscure errors at an earlier stage, lowering costs and improving quality as a result. 

In this tutorial, we will use examples to show how developers write QuickCheck specifications—which are actually Erlang programs using the QuickCheck API—and use them to test code written in Erlang or other programming languages. We will show how QuickCheck’s shrinking finds tiny examples that provoke errors, making the step from observing a bug to diagnosing it very short indeed, and we will show how property driven development can produce code that is solid from the word go.

Tutorial: Testing concurrent software with QuickCheck

Testing software is difficult, testing concurrent software seems almost impossible. Just writing a test case for a concurrent program is a challenge, since one may have a number of different correct executions that result in different, but all correct results. 

Quviq QuickCheck is an automated testing tool that can be used to automatically generate test cases. In traditional testing, one often writes a sequence of operations to be executed and that sequence is tested. Running the commands in that sequence in parallel is far harder, since how would the test case look like?  QuickCheck specification also often start from specifying sequential execution of possible sequences; but QuickCheck can run the commands in the sequence in parallel and the specification can be used to validate the outcome of such a run. All that, fully automatically.
In this way, testing the Erlang OTP dets module becomes possible.

PULSE is an addition to QuickCheck that enables you to find concurrency errors like race conditions and deadlocks in Erlang programs. Even if those errors may not show on a single processor system, they may be sitting there waiting to be revealed when you switch to multi-core. With PULSE you explore random schedulings that are possible on a multi-core but not on a single core, therewith increasing the possibility to reveal weird errors. Of course, the test case is minimized when finding a concurrency error, which results in a repeatable test case that helps to analyze the cause of the error quickly.

In this tutorial some knowledge of QuickCheck is required; it suffices if you participated in a QuickCheck talk or tutorial before. We will look at a few examples in which QuickCheck and PULSE are used to find concurrency errors.

BoF - Erlang and TDD

A discussion group on Erlang and Test Driven Development.
Thomas Arts is Host to the Following Tracks

Erlang has been used for testing commercial products, both those written in Erlang - not least Erlang/OTP itself, and other languages, C and Java included. Research on Erlang and model-based testing has gone on for over a decade, with the EU recognizing this by funding the ProTest, project, a 2.5 million euro grant focused on Erlang and Property based testing. This track  covers hands-on practical industrial use cases, tools as well as the latest news from the research front.