Mac OS Catalina can build wheel but not install it?

[jjfiv]

First off, Maturin is great software.

I have a CI suite (for https://github.com/jjfiv/fastrank). that just stumbled over github actions removal of Mac OS 10.14. The relevant action is here:

      - name: py-install
        run: |
          pip install -r requirements.txt
          pip install maturin
          maturin build --release
          pip install target/wheels/fastrank*.whl

I then run some unit-tests and upload the wheels as artifacts.... but now I'm getting this:

 Successfully installed maturin-0.7.7 toml-0.10.0
WARNING: You are using pip version 20.0.1; however, version 20.0.2 is available.
You should consider upgrading via the '/Users/runner/hostedtoolcache/Python/3.5.9/x64/bin/python -m pip install --upgrade pip' command.
🍹 Building a mixed python/rust project
🐍 Using CPython 3.5m at python3 to generate the cffi bindings
📦 Built source distribution to /Users/runner/runners/2.164.0/work/fastrank/fastrank/target/wheels/fastrank-0.5.0.tar.gz
   Compiling fastrank v0.5.0 (/Users/runner/runners/2.164.0/work/fastrank/fastrank)
    Finished release [optimized] target(s) in 18.19s
📦 Built wheel to /Users/runner/runners/2.164.0/work/fastrank/fastrank/target/wheels/fastrank-0.5.0-py2.py3-none-macosx_10_7_x86_64.whl
ERROR: fastrank-0.5.0-py2.py3-none-macosx_10_7_x86_64.whl is not a supported wheel on this platform.
WARNING: You are using pip version 20.0.1; however, version 20.0.2 is available.
You should consider upgrading via the '/Users/runner/hostedtoolcache/Python/3.5.9/x64/bin/python -m pip install --upgrade pip' command.
##[error]Process completed with exit code 1.

Any advice on how to debug: -none-macosx_10_7_x86_64.whl is not a supported wheel on this platform? I'm using -b cffi if that matters.

Is maybe the -macosx_10_7_x86_64 no longer true on Catalina? I don't have a local Mac I can upgrade to test.

[jjfiv]

Update:
My local python has a lot of supported "py3" vague version models, e.g., with pip debug --verbose. These appear to not be visible via the same command on the github actions runners in Catalina. Looking into this / maybe they're gone on purpose?

My crate uses cffi and so I might need to copy/rename it for the many cp3x variants still available.

[jjfiv]

Turns out this is a pip bug: pip install --upgrade pip seems to have gotten me past it: pypa/pip#7626