CppQuickCheck

ABOUT

CppQuickCheck is a library for automated testing of C++ code. You provide a specification how your code is supposed to behave through properties and CppQuickCheck will generate a large number of random test cases that attempt to prove or disprove the properties. The specifications are written in pure C++ using the functionality of the CppQuickCheck library.

DOCUMENTATION

You can find examples in 'examples/src'.

BACKGROUND

CppQuickCheck is inspired and based on the QuickCheck library for Haskell. CppQuickCheck differs in some aspects of the implementation and interface (as well as being written in C++ instead of Haskell), but tries to maintain similar functionality to the QuickCheck library.

A similar library for C++ exists called QuickCheck++. QuickCheck++ does not support several important things that the Haskell QuickCheck supports including:

• Generator combinators - In QuickCheck++ custom generators for user defined types are written by hand, with no provided random number generation facility. One example of a way that Haskell's QuickCheck (and CppQuickCheck) improve on this is the function oneof whick takes a list of generators and creates a new generator that when called, selects a random generator from the list and uses that to generate the input. In QuickCheck++ this has to be written by hand using some external random number generating library.
• Shrinking the input for failed test cases - When a randomly generated test case fails, Haskell's QuickCheck (and CppQuickCheck, but not QuickCheck++) will try to shrink the input to provide a minimal failing case. This makes debugging the failure easier because instead of working with a potentially large input case, much of the input can be removed to reveal the structure of the failure.

For these reasons, CppQuickCheck tries to maintain all the functionality of the Haskell QuickCheck, and so taking a different implementation approach than QuickCheck++.

UNIT TESTS

Unit tests exists in the directory 'test'.

$ mkdir -p build
$ cd build
$ cmake ..
$ make check

To get a more detailed output, rerun it with

$ ./all-catch-tests

It uses the test framework Catch2. Run ./all-catch-tests --help to see the command line options.

CONTRIBUTING

Please direct your pull requests to https://github.com/philipp-classen/CppQuickCheck, which is the repository where the active development takes place.

Currently, CppQuickCheck uses C++11 but not C++14. Travis will compile the library and run the tests with GCC 4.9 and Clang 3.8.

The code is autoformatted with clang-format using the predefined Chromium style.

If you have a pull request, it is not mandatory to match those rules perfectly, but if you have clang-format already installed, you can run the formatter locally with make clangformat:

$ mkdir -p build
$ cd build
$ cmake ..
$ make clangformat

Hint: In general, clang-format is quite smart, but for rare exceptions like 3rd party libraries you can disable it like this:

// clang-format off
... some code not to the touched ...
// clang-format on

LICENSE

CppQuickCheck is distributed under a BSD license (see LICENSE).