Testing with Axioms in C++ 2011.

Abstract

Unit testing is an important part of modern software development, where individual code units are tested in isolation. Such tests are typically case-based, checking a likely error scenario or an error that has previously been identified and fixed. Coming up with good test cases is challenging, particularly when testing generic code, and focusing on individual tests can distract from creating tests that cover the full functionality.Concepts provide a generic way of describing code interfaces for generic code. Together with axioms, program behaviour can be specified algebraically in a formal or semi-formal way.In this paper we show how concepts and axioms can be expressed in standard C++ 2011, and explore how to generate generic unit tests, by treating the axioms as code to be evaluated with test data. We also show a generic way to generate test data for axiom-based testing in C++ 2011.

Specification of generic APIs, or

“…Although the proposal was ultimately rejected, the specification features as well as most of the other features can be provided through libraries such as the Catsfoot C++ template library [2].…”

Revisiting Language Support for Generic Programming: When Genericity Is a Core Design Goal

“…C ++ 20 implements a scaled back version of C ++ 0x's concepts which does not provide support for semantic constraints-but only for same-type constraints and API modeling constraints. Bagge et al previously built a testing system atop concepts and axioms implemented using template metaprogramming in C ++ 11 [4].…”

“…These formulas are boolean expressions with free variables, thus encompassing equational and conditional equational specifications as common in algebraic specifications [10]. Boolean expressions have the benefit of being readily handled by programming language compilers and tools, allowing us to compile axioms as test oracles and systematically test a program's compliance with its specification [4]. The axiom formalism and the program code are semantically compatible, thus avoiding the semantic gap mentioned previously [78].…”

Towards safer programming language constructs

“…(a<b) || pair(a, 0)<pair(b, 0) -or a similar formula in a general case. Furthermore, we are intended to apply axiom-based test generation [112]. Thus the test cases could be more automated.…”