Catch VS doctest

This is one area where a BDD style framework like catch2[0] really shines, IMO. The way tests are written in this style naturally lends itself to self-documenting each branch

[0]: https://github.com/catchorg/Catch2

The code uses catch2 to test for correctness and performance. Catch2 is a unit testing framework for C++, but it also provides basic micro-benchmarking features. Unfortunately, it doesn't provide any way to visualise the results, so I created a script and submitted PR adding plotting capabilities to Catch.

https://github.com/catchorg/Catch2 (for unit testing, need to do timing yourself)

```c++ // https://github.com/catchorg/Catch2/tree/Catch1.x // https://github.com/philsquared/Catch/releases/download/v1.12.2/catch.hpp

Include(FetchContent) FetchContent_Declare(Catch2 GIT_REPOSITORY https://github.com/catchorg/Catch2.git GIT_TAG v3.3.2 ) FetchContent_MakeAvailable(Catch2)

Another possible issue would be the include(Catch) in your root cmakelists.txt . To include Catch there it must be part of your module path. Otherwise you have to include the path to that catch2 cmake file. Here is that file in their repository - https://github.com/catchorg/Catch2/blob/devel/extras/Catch.cmake . I recon that CMake doesn't know about this file since you call find_package(Catch2 REQUIRED) later in your subdirectory

catch2 has become fairly bloated. doctest takes all of the best parts of catch2 without all the bloat and the end result is a test framework that is literally over 10x faster than catch2. It's also like 90% compatible with catch2 so porting your tests to it is pretty easy.

Especially if you have a build process that always runs your unit tests, it's nice to have a very fast test/compile/debug loop.

https://github.com/doctest/doctest

I have never used "tools" for unit-tests, only web sites that show the results of the tests or code coverage. For C++ I prefer https://github.com/doctest/doctest but most companies I worked for use Catch2.

Do the README and tutorial not explain it well enough? It's a framework for automated unit testing.

This is, honestly, super easy to get going. Nowadays you have a ton of libraries and more-than-decent build systems. With Meson/CMake and Conan/Vcpkg I can set up a project with testing in 3 minutes. Also, I think that at the end of the day you want your tests to live somewhere else. But if you want to embed them, you also have https://github.com/doctest/doctest.

Write some tests. They can find bugs early and give you confidence that your code works so far. That doesn't have to be anything fancy, e.g. with doctest:

Keep in mind https://github.com/doctest/doctest/issues/554. Also, doctest lacks: - Matchers - Data generators - Benchmarking - ...

Your requirements can easily simulated on paper (like increase the speed once, twice, ...), then translated to unit-tests with a framework like https://github.com/doctest/doctest.

For stuff like this which is very easy to test (very predefined input vs output), I highly suggest using some testing framework. Catch2 is great, but there is also doctest and good ole googletest. If you do this, it would also be a great intro to CI, where you do some plumbing on github or gitlab where every commit causes a build to happen on their servers and run through the unit tests, and if it passes it gets merged into master.