pdm seems unable to install a dependency from an egg present on pypi.org

[lestephane]

Running pdm install on Linux with a 3.10 python and the following dependency:

dependencies = ["beancount==2.3.5"]

Based on what I see at https://pypi.org/project/beancount/2.3.5/#files

I would have expected https://files.pythonhosted.org/packages/e1/77/fcb9c7d46a16acc55a5da9395a24ec0d65cb72987426d3edb317d58d167e/beancount-2.3.5-py3.10-linux-x86_64.egg to be used.

Instead it tries to compile from source distribution https://files.pythonhosted.org/packages/77/51/2acc2741fa2937a3a1123fd00e6e76e6d6f27c46579ea53705c49bd221ec/beancount-2.3.5.tar.gz

...
building 'beancount.parser._parser' extension
x86_64-linux-gnu-gcc -Wno-unused-result -Wsign-compare -DNDEBUG -g -fwrapv -O2 -Wall -g -fstack-protector-strong -Wformat -Werror=format-security -g -fwrapv -O2 -fPIC -DBEANCOUNT_VERSION=2.3.5 -DVC_CHANGESET= 
-DVC_TIMESTAMP=0 -DPARSER_SOURCE_HASH -I. -I/home/scrubbed/Project/.direnv/python-3.10.6/include -I/usr/include/python3.10 -c beancount/parser/decimal.c -o 
build/temp.linux-x86_64-cpython-310/beancount/parser/decimal.o -std=gnu99
beancount/parser/decimal.c:2:10: fatal error: Python.h: No such file or directory
    2 | #include <Python.h>
      |          ^~~~~~~~~~
compilation terminated.
error: command '/usr/bin/x86_64-linux-gnu-gcc' failed with exit code 1

And I don't want that. I no longer want to pollute my host operating system with -dev packages if there is a perfectly valid binary package with published checksums.

The following works (though the sha256 fragment is ignored unfortunately)

dependencies = [
    "beancount @ https://files.pythonhosted.org/packages/e1/77/fcb9c7d46a16acc55a5da9395a24ec0d65cb72987426d3edb317d58d167e/beancount-2.3.5-py3.10-linux-x86_64.egg#sha256=8a7d360101ad278294d10109527ac5b2bfbb3707994ccb77b895b195e2c81415"
]

But it feels wrong somehow, because:

• It displays at the end: ✔ Install beancount **0.0.0** successful (0.0.0 is incorrect)
• It will try to install the py3.10-linux-x86_64.egg even on other OSes and / or python versions. And the following is not possible at the moment (to my knowledge)

dependencies = [
    'beancount @ https://files.pythonhosted.org/packages/e1/77/fcb9c7d46a16acc55a5da9395a24ec0d65cb72987426d3edb317d58d167e/beancount-2.3.5-py3.10-linux-x86_64.egg; python_version ~= "3.10" and platform_system == "Linux"',
    'beancount==2.3.5; platform_system != "Linux"'
]

Is there a way for pdm to pick up the egg (if present for the OS and python version) as a fallback for when a wheel is not available? That would be my expectation, at least when I use PDM_ONLY_BINARY=:all:.