Latest release broke installation under Windows

[darosior]

I'm using Coincurve in my BIP32 package. Following a request from @MementoRC i was in the process of bumping the maximum supported Coincurve version to 0.19 (darosior/python-bip32#40) when my CI caught that installing Coincurve under Windows was broken (see here for the installation instructions).

First of all, cffi was missing. Adding a temporary commit to manually install cffi to make sure it was the only issue revealed at runtime that Coincurve wasn't correctly installed (see here for the CI job):

Traceback (most recent call last):
  File "D:\a\python-bip32\python-bip32\setup.py", line 2, in <module>
    import bip32
  File "D:\a\python-bip32\python-bip32\bip32\__init__.py", line 1, in <module>
    from .bip32 import BIP32, PrivateDerivationError, InvalidInputError
  File "D:\a\python-bip32\python-bip32\bip32\bip32.py", line 5, in <module>
    from .utils import (
  File "D:\a\python-bip32\python-bip32\bip32\utils.py", line 1, in <module>
    import coincurve
  File "C:\hostedtoolcache\windows\Python\3.9.13\x64\lib\site-packages\coincurve\__init__.py", line 1, in <module>
    from coincurve.context import GLOBAL_CONTEXT, Context
  File "C:\hostedtoolcache\windows\Python\3.9.13\x64\lib\site-packages\coincurve\context.py", line 5, in <module>
    from coincurve.flags import CONTEXT_ALL, CONTEXT_FLAGS
  File "C:\hostedtoolcache\windows\Python\3.9.13\x64\lib\site-packages\coincurve\flags.py", line 3, in <module>
    CONTEXT_SIGN = lib.SECP256K1_CONTEXT_SIGN
  File "C:\hostedtoolcache\windows\Python\3.9.13\x64\lib\site-packages\cffi\api.py", line 912, in __getattr__
    make_accessor(name)
  File "C:\hostedtoolcache\windows\Python\3.9.13\x64\lib\site-packages\cffi\api.py", line 907, in make_accessor
    raise AttributeError(name)
AttributeError: SECP256K1_CONTEXT_SIGN

[ofek]

@MementoRC

[MementoRC]

@ofek @darosior Started to look at it

[ecy777]

I'm having the same problem too

[ofek]

Yanked:

[MementoRC]

@ofek The issue must be with the _windows_libsecp256k1.py. It is unclear how all the tests on windows for the conda feedstock did not highlight this issue if CFFI does not handle #define (formulae) correctly. I ran all the coincurve tests successfully for the feedstock
I proposed a PR: #135

It includes more than just the windows fix, please review and let me know if you prefer to separate it

[darosior]

Hey there, any update on this issue?

[ofek]

Fixed: https://github.com/ofek/coincurve/releases/tag/v19.0.1