PyPI 2.2.0 source distribution missing `PyCustomMessageBuilder.h`

[hillnich]

My team does our release builds in a manylinux2014 environment. Since 2.1.0, it appears pycapnp is no longer released with manylinux2014 binary wheels. As such, we've been successfully building with the 2.1.0 source distribution. 2.2.0 does not appear to build though. We keep getting the following error:

      g++ -pthread -B /usr/local/src/miniconda3/envs/_dev/compiler_compat -fno-strict-overflow -Wsign-compare -DNDEBUG -O2 -Wall -fPIC -O2 -isystem /usr/local
/src/miniconda3/envs/_dev/include -fPIC -O2 -isystem /usr/local/src/miniconda3/envs/_dev/include -fPIC -I. -I/tmp/pip-install-_p5evyha/pycapnp_a0332435d867403
a89059a9e219f1f56/build64/include -I/usr/local/src/miniconda3/envs/_dev/include/python3.12 -c capnp/includes/PyCustomMessageBuilder.cpp -o build/temp.linux-x8
6_64-cpython-312/capnp/includes/PyCustomMessageBuilder.o --std=c++14
      capnp/includes/PyCustomMessageBuilder.cpp:1:10: fatal error: PyCustomMessageBuilder.h: No such file or directory
          1 | #include "PyCustomMessageBuilder.h"
            |          ^~~~~~~~~~~~~~~~~~~~~~~~~~
      compilation terminated.
      error: command '/opt/rh/devtoolset-10/root/usr/bin/g++' failed with exit code 1
      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
  ERROR: Failed building wheel for pycapnp
Failed to build pycapnp

I downloaded and unpacked the tarball from PyPI at url: https://files.pythonhosted.org/packages/9b/96/0b1696ed89950b34506594a2c1f0c19c31d91385dfee81295113e9f22442/pycapnp-2.2.0.tar.gz

It indeed appears to be missing the PyCustomMessageBuilder.h that is found in the repo at <repo root>/capnp/includes:

(_dev) [root@733475]# ls /root/workspace/pycapnp/pycapnp-2.2.0/capnp/includes
capnp_cpp.pxd  __init__.pxd  PyCustomMessageBuilder.cpp  schema_cpp.pxd  types.pxd

[haata]

I suspect https://github.com/capnproto/pycapnp/blob/master/MANIFEST.in is what needs to be fixed.

And yes we don't build with manylinux2014 (I believe there were some issues using it and supporting some other architectures like aarch64, but it's been a while) as it's been EOL since mid last year (https://github.com/mayeut/pep600_compliance/blob/master/EOL.rst).

I might be able to look at this later in the week, though I'm happy to accept a PR in the meantime.

[BrianXu0623]

Created a PR for resolving this issue.

I added the py_custom_message_builder.h to the binary output. Hopefully it can resolve the issue, but I cannot find a way to validate it.
Hope @haata @hillnich can help to find an approach.

[haata]

Thanks! Should part of v2.2.1