First of all, it's suggested to compile the tests in release mode unless you plan to debug a single test case. Since some modules involve intensive computation and it's too slow to run the whole test in debug mode.

After compiling the test, you'll find a runtest executable in the binary output directory.

Testing in Euclid is powered by Catch2, which is already bundled in Euclid. It provides a lot of convenient ways to run the test.

You can execute runtest without any command line argument to run the whole test.

Other than that, you could run the test on a whole module like

1 runtest "[math]"

to test all the submodules in the math module. Or test a single submodule directly,

1 runtest "[vector]"

And you can run a single test section like

1 runtest "[vector]" -c "length"

For more command line options, please refer to the Catch2 documentation.