How to merge Doxygen snippets?

I have a project using Doxygen, Breathe, and Sphinx for documentation. The hardcoded example snippets of code in the documentation have become a pain to maintain, as the project is constantly evolving. I want to make the example snippets be covered by our automated tests.

I experimented with \example, \include, \snippet, and \dontinclude, but each of them seem to have problems:

• \example and \include only allow you to paste the entire contents of a file into a code block. Since I don't want to have #include example_foo.cpp show up at the top of every example in the documentation, these directives aren't of any help.
• \snippets don't seem to be mergeable into a single code block.
• \dontinclude uses \skip and \until, but their search pattern is displayed in the code block.

I am not interested in any of the directives that require you to hardcode the line numbers, since that's very brittle.

Of these, \snippet seems the most promising and useful:

But I'd like to merge the snippets, since these separate code blocks look ugly.

I've created a minimal reproducible example repository here:

.
├── Dockerfile
├── docs
│   ├── conf.py
│   ├── doxygen
│   │   └── Doxyfile
│   └── index.rst
├── example
│   └── nums.cpp
├── nums
│   └── nums_struct.hpp
└── README.md

example/nums.cpp:

//! [one]
int one() {
    return 1;
}
//! [one]

int hidden() {
    return 42;
}

//! [two]
int two() {
    return 2;
}
//! [two]

int main() {
    return one() + two();
}

nums/nums_struct.hpp:

/// \snippet nums.cpp one
/// \snippet nums.cpp two
struct nums_struct
{};

I'm on Arch Linux, but the command sudo docker build . -t hello && sudo docker run -v .:/example hello should work on other Linux distros out of the box, with Docker as the only dependency. It outputs docs/_build/html/index.html, which you can view using your browser.

There was a similar question in 2017 titled Is there a way to merge snippets or make a disjoint snippet in Doxygen?, but it didn't get any answers.

Thanks to @albert for nudging me in the right direction.

His answer does not handle functions containing braces, like if-statement curly braces that indicate the start and stop of the scope.

I figured out that by placing the end marker (//! [stop_one] here) at the end of a line of code, we can prevent a second newline from appearing in the docs.

So using this nums/nums_struct.hpp:

/// \dontinclude nums.cpp
/// \skipline start_one
/// \until stop_one
/// \skipline start_two
/// \until stop_two
struct nums_struct
{};

and this example/nums.cpp:

//! [start_one]
int one() {
    if (1) {
        return 1;
    }
    return 1;
} //! [stop_one]

int hidden() {
    return 42;
}

//! [start_two]
int two() {
    return 2;
} //! [stop_two]

int main() {
    return one() + two();
}

we can get the output I was originally looking for: