118 research outputs found
Tester versus Bug: A Generic Framework for Model-Based Testing via Games
We propose a generic game-based approach for test case generation. We set up
a game between the tester and the System Under Test, in such a way that test
cases correspond to game strategies, and the conformance relation ioco
corresponds to alternating refinement. We show that different test assumptions
from the literature can be easily incorporated, by slightly varying the moves
in the games and their outcomes. In this way, our framework allows a wide
plethora of game-theoretic techniques to be deployed for model based testing.Comment: In Proceedings GandALF 2018, arXiv:1809.0241
Towards an I/O Conformance Testing Theory for Software Product Lines based on Modal Interface Automata
We present an adaptation of input/output conformance (ioco) testing
principles to families of similar implementation variants as appearing in
product line engineering. Our proposed product line testing theory relies on
Modal Interface Automata (MIA) as behavioral specification formalism. MIA
enrich I/O-labeled transition systems with may/must modalities to distinguish
mandatory from optional behavior, thus providing a semantic notion of intrinsic
behavioral variability. In particular, MIA constitute a restricted, yet fully
expressive subclass of I/O-labeled modal transition systems, guaranteeing
desirable refinement and compositionality properties. The resulting modal-ioco
relation defined on MIA is preserved under MIA refinement, which serves as
variant derivation mechanism in our product line testing theory. As a result,
modal-ioco is proven correct in the sense that it coincides with traditional
ioco to hold for every derivable implementation variant. Based on this result,
a family-based product line conformance testing framework can be established.Comment: In Proceedings FMSPLE 2015, arXiv:1504.0301
Recommended from our members
Combining centralised and distributed testing
Many systems interact with their environment at distributed interfaces (ports) and sometimes it is not possible to place synchronised local testers at the ports of the system under test (SUT). There are then two main approaches to testing: having independent local testers or a single centralised tester that interacts asynchronously with the SUT. The power of using independent testers has been captured using implementation relation \dioco. In this paper we define implementation relation \diococ for the centralised approach and prove that \dioco and \diococ are incomparable. This shows that the frameworks detect different types of faults and so we devise a hybrid framework and define an implementation relation \diocos for this. We prove that the hybrid framework is more powerful than the distributed and centralised approaches. We then prove that the Oracle problem is NP-complete for \diococ and \diocos but can be solved in polynomial time if we place an upper bound on the number of ports. Finally, we consider the problem of deciding whether there is a test case that is guaranteed to force a finite state model into a particular state or to distinguish two states, proving that both problems are undecidable for the centralised and hybrid frameworks
Towards Symbolic Model-Based Mutation Testing: Combining Reachability and Refinement Checking
Model-based mutation testing uses altered test models to derive test cases
that are able to reveal whether a modelled fault has been implemented. This
requires conformance checking between the original and the mutated model. This
paper presents an approach for symbolic conformance checking of action systems,
which are well-suited to specify reactive systems. We also consider
nondeterminism in our models. Hence, we do not check for equivalence, but for
refinement. We encode the transition relation as well as the conformance
relation as a constraint satisfaction problem and use a constraint solver in
our reachability and refinement checking algorithms. Explicit conformance
checking techniques often face state space explosion. First experimental
evaluations show that our approach has potential to outperform explicit
conformance checkers.Comment: In Proceedings MBT 2012, arXiv:1202.582
IST Austria Technical Report
Model-based testing is a promising technology for black-box software and hardware testing, in which test cases are generated automatically from high-level specifications. Nowadays, systems typically consist of multiple interacting components and, due to their complexity, testing presents a considerable portion of the effort and cost in the design process. Exploiting the compositional structure of system specifications can considerably reduce the effort in model-based testing. Moreover, inferring properties about the system from testing its individual components allows the designer to reduce the amount of integration testing.
In this paper, we study compositional properties of the IOCO-testing theory. We propose a new approach to composition and hiding operations, inspired by contract-based design and interface theories. These operations preserve behaviors that are compatible under composition and hiding, and prune away incompatible ones. The resulting specification characterizes the input sequences for which the unit testing of components is sufficient to infer the correctness of component integration without the need for further tests. We provide a methodology that uses these results to minimize integration testing effort, but also to detect potential weaknesses in specifications. While we focus on asynchronous models and the IOCO conformance relation, the resulting methodology can be applied to a broader class of systems
Monadic Sequence Testing and Explicit Test-Refinements
We present an abstract framework for sequence testing that is implemented in Isabelle/HOL-TestGen. Our framework is based on the theory of state-exception monads, explicitly modelled in HOL, and can cope with typed input and output, interleaving executions including abort, and synchronisation. The framework is particularly geared towards symbolic execution and has proven effective in several large case-studies involving system models based on large (or infinite) state. On this basis, we rephrase the concept of test-refinements for inclusion, deadlock and IOCO-like tests, together with a formal theory of its rela- tion to traditional, IO-automata based notions
Bisimilar States in Uncertain Structures
We provide a categorical notion called uncertain bisimilarity, which allows to reason about bisimilarity in combination with a lack of knowledge about the involved systems. Such uncertainty arises naturally in automata learning algorithms, where one investigates whether two observed behaviours come from the same internal state of a black-box system that can not be transparently inspected. We model this uncertainty as a set functor equipped with a partial order which describes possible future developments of the learning game. On such a functor, we provide a lifting-based definition of uncertain bisimilarity and verify basic properties. Beside its applications to Mealy machines, a natural model for automata learning, our framework also instantiates to an existing compatibility relation on suspension automata, which are used in model-based testing. We show that uncertain bisimilarity is a necessary but not sufficient condition for two states being implementable by the same state in the black-box system. We remedy the lack of sufficiency by a characterization of uncertain bisimilarity in terms of coalgebraic simulations
Bisimilar States in Uncertain Structures
We provide a categorical notion called uncertain bisimilarity, which allows
to reason about bisimilarity in combination with a lack of knowledge about the
involved systems. Such uncertainty arises naturally in automata learning
algorithms, where one investigates whether two observed behaviours come from
the same internal state of a black-box system that can not be transparently
inspected. We model this uncertainty as a set functor equipped with a partial
order which describes possible future developments of the learning game. On
such a functor, we provide a lifting-based definition of uncertain bisimilarity
and verify basic properties. Beside its applications to Mealy machines, a
natural model for automata learning, our framework also instantiates to an
existing compatibility relation on suspension automata, which are used in
model-based testing. We show that uncertain bisimilarity is a necessary but not
sufficient condition for two states being implementable by the same state in
the black-box system. To remedy the failure of the one direction, we
characterize uncertain bisimilarity in terms of coalgebraic simulations
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