PyPI Source Dist is broken

[tdubose]

As it says in the title, the current version of halide on PyPI-test (16.0.0) is broken for source dists.

This can be replicated on a system for which no prebuilt wheel is available (or using -no-binary); I'm using macOS 13.3 and python 3.10. The error is occurring due to a CMake path-finding issue:

CMake Error at CMakeLists.txt:55 (find_package):
        By not providing "FindHalide.cmake" in CMAKE_MODULE_PATH this project has
        asked CMake to find a package configuration file provided by "Halide", but
        CMake did not find one.

        Could not find a package configuration file provided by "Halide" with any
        of the following names:

          HalideConfig.cmake
          halide-config.cmake

Is it even possible to make this work out of the box, given the requirement for non-standard LLVM?

In any case, it would be nice at least if pip raised an error, or e.g. if source dists were disallowed entirely.

[alexreinking]

Is it even possible to make this work out of the box, given the requirement for non-standard LLVM?

We would need to split things into three packages:

1. halide-llvm: the build of LLVM as-used by Halide
2. halide-bin: the C++ library and CMake helpers
3. halide: the Python bindings.

Each one depends on the previous.

(1) is the difficult part since LLVM's build is so time-consuming.

[alexreinking]

or e.g. if source dists were disallowed entirely

In #8405 we decided against providing sdists because getting the dependencies right is too hard.

[tdubose]

@alexreinking Great news, very excited to start pip install-ing Halide!