How to build an executable while installing in normal and editable mode

Hello, I'm currently learning how to use CMake and pybind11 with this project. As part of the installation process, I need to build and install a C++ source file. To ensure that everything is clear, I've included the reproduction code below.

Description

My project structure: It's basically the same except there is my cpp source file helloworld.cpp in src/ folder.

$ tree -L 2
.
├── CMakeLists.txt
├── pybind11
├── pyproject.toml
├── setup.py
└── src
├── helloworld.cpp
└── main.cpp

src/helloworld.cpp: A trivial helloworld program. $ cat src/helloworld.cpp
```
#include <iostream>
```

int main(int argc, char **argv) { std::cout << "Hello World!!!\n"; return 0; }

- `CMakeLists.txt`: It's basically the same as [CMakeLists.tx](https://github.com/pybind/cmake_example/blob/master/CMakeLists.txt) except `add_executable(helloworld src/helloworld.cpp)` is added to build executable.

$ cat CMakeLists.txt cmake_minimum_required(VERSION 3.22) project(cmake_example)

add_executable(helloworld src/helloworld.cpp)

add_subdirectory(pybind11) pybind11_add_module(cmake_example src/main.cpp)

target_compile_definitions(cmake_example PRIVATE VERSION_INFO=${EXAMPLE_VERSION_INFO})

- `pyproject.toml`:

$ cat pyproject.toml [build-system] requires = ["setuptools>=62.0.0", "wheel", "cmake>=3.22"] build-backend = "setuptools.build_meta"

- `pybind11` is a git submodule, and `setup.py` is exactly the same as this [setup.py](https://github.com/pybind/cmake_example/blob/master/setup.py).

#### Build in normal mode.
- Create virtual env and update pip: `python3 -m venv venv && source venv/bin/activate && python3 -m pip install --upgrade pip`
- Install in normal mode: `python3 -m pip install .` 
- `cmake_example` library is installed correctly but my `helloworld` program is not. There is no `helloworld` program in `venv`.

$ ls venv/lib/python3.8/site-packages/ cmake_example-0.0.1.dist-info
cmake_example.cpython-38-x86_64-linux-gnu.so


#### Build in editable mode.
- Create virtual env and update pip: `python3 -m venv venv && source venv/bin/activate && python3 -m pip install --upgrade pip`
- Install in editable mode: `python3 -m pip install -e .` 
- `cmake_example` library is also installed correctly but my `helloworld` program is not. There is no `helloworld` program created in the current folder.

$ ls cmake_example.cpython-38-x86_64-linux-gnu.so cmake_example.egg-info CMakeLists.txt pybind11 pyproject.toml setup.py src venv


#### My experiment:
I actually tried to make it work by modifying `setup.py` with the following way.
- Add code snippet in `setup.py` in Line:47.

    bindir = extdir / "bin"
    print(f"User's executables resides in {bindir}")
    cmake_args = [
        # My innovation. helloworld can be called in scripts.
        f"-DCMAKE_RUNTIME_OUTPUT_DIRECTORY={bindir}{os.sep}",
        f"-DCMAKE_LIBRARY_OUTPUT_DIRECTORY={extdir}{os.sep}",
        f"-DPYTHON_EXECUTABLE={sys.executable}",
        f"-DCMAKE_BUILD_TYPE={cfg}",  # not used on MSVC, but no harm
    ]


This approach kind of work. Now I can do `pip install .` and `helloworld` program appears in `venv/lib/python3.8/site-packages/bin/helloworld`. However, this approach doesn't work in editable model. I.e., I do `pip install -e .`, but `helloworld` program is no created anywhere in the project.

My question is how to achieve the following goal: I would like the `helloworld` program to be created automatically when I run `pip install .` and `pip install -e .`, and I want this program to be installed in the correct Python root path in both modes. Do you have any suggestions or advice on how I can make this happen? Thank you for your help!

**System info:**
OS: ubuntu20.04
Python: Python3.8

@lionlai1989

I did something similar yesterday, by adding set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}) to cmake, executables were added to pip wheel.

Example code: https://github.com/cubao/cubao-tippecanoe/blob/pypi-release/CMakeLists.txt

$ unzip -l dist/cubao_tippecanoe-0.0.1-cp310-cp310-linux_x86_64.whl
Archive:  dist/cubao_tippecanoe-0.0.1-cp310-cp310-linux_x86_64.whl
  Length      Date    Time    Name
---------  ---------- -----   ----
  1773952  2023-09-17 15:38   __cubao_tippecanoe_decode.exe
  1301248  2023-09-17 15:38   __cubao_tippecanoe_enumerate.exe
    78640  2023-09-17 15:38   __cubao_tippecanoe_jsontool.exe
   537496  2023-09-17 15:38   __cubao_tippecanoe_overzoom.exe
  2123648  2023-09-17 15:38   __cubao_tippecanoe_tile-join.exe
  2657384  2023-09-17 15:38   __cubao_tippecanoe_tippecanoe.exe
   175960  2023-09-17 15:38   _pybind11_tippecanoe.cpython-310-x86_64-linux-gnu.so
       95  2023-09-17 09:11   cubao_tippecanoe/__init__.py
      687  2023-09-17 15:31   cubao_tippecanoe/__main__.py
     1329  2023-09-17 15:38   cubao_tippecanoe-0.0.1.dist-info/LICENSE.md
    63751  2023-09-17 15:38   cubao_tippecanoe-0.0.1.dist-info/METADATA
      105  2023-09-17 15:38   cubao_tippecanoe-0.0.1.dist-info/WHEEL
       17  2023-09-17 15:38   cubao_tippecanoe-0.0.1.dist-info/top_level.txt
     1259  2023-09-17 15:38   cubao_tippecanoe-0.0.1.dist-info/RECORD
---------                     -------
  8715571                     14 files

pybind / cmake_example

How to build an executable while installing in normal and editable mode #132

Description