I'm writing an external library (a component controller) for use with mbed 5 and plan to make it available in the mbed repositories. I want to write tests to confirm that my code is working properly, but they're just regular ordinary unit tests and don't need to be run on an embedded controller. I'm looking at Catch as my framework, which provides a main for the test suite.
When I build my project with the mbed CLI or Eclipse CDT (using an exported project), what .cpp files are included, and what .o files are linked into the embedded image? Does the image only include code pulled in from my main.cpp file via includes, or does it compile and link all of the .cpp files visible (potentially including my test cases)? If the latter, is there a clean way to exclude them that won't collide with the built-in utest functionality?
All .cpp files are included, but there are some exceptions. FEATURE_ and TARGET_ folders are special, and are only added when your board has a certain feature (or is part of a certain target). I think there's something special about TESTS as well.
You can see the exact commands that are fed into the compiler / linker via mbed compile -v, or if you want a neat list, export to a makefile via mbed export -i make_gcc_arm, which will list all files.
If you want to learn more about the inner specifics, or want to script around these, all logic is implemented in a Python module, and you can use this in your own Python scripts to get lists of headers / symbols / defines / etc. that will be included. For example, see vscode/__init.py__.
Note: if you want to exclude a certain file or folder, you can do so via .mbedignore.