poetry install does not use available binary for numpy 1.19.2

[pederpansen]

• [x] I am on the latest Poetry version.
• [x] I have searched the issues of this repo and believe that this is not a duplicate.
• [x] If an exception occurs when executing a command, I executed it again in debug mode (-vvv option).
• OS version and name: Mac OS 10.15.6
• Poetry version: 1.1.2
• Link of a Gist with the contents of your pyproject.toml file: https://gist.github.com/pederpansen/eb25acdfea2bc808fa907e31ee541da1

Issue

When running poetry install the installation of numpy 1.19.2 (using pyenv-installed Python 3.8.2) takes very long (~minutes) and seems to compile from source.

However, running pip install numpy==1.19.2 yields

Collecting numpy==1.19.2
  Using cached https://files.pythonhosted.org/packages/33/1a/d10d1c23d21c289a3e87e751a9daf0907e91665cab08d0c35033fd4f5b55/numpy-1.19.2-cp38-cp38-macosx_10_9_x86_64.whl
Installing collected packages: numpy
Successfully installed numpy-1.19.2
WARNING: You are using pip version 19.2.3, however version 20.2.3 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.

within a few seconds.

[naveen521kk]

Did you install python 3.9 and did poetry created a venv with that?
In that is the case it is expected.

[jtc42]

We're also having this problem now which is causing significant delays in releasing a critical update.

Log available online if it's useful https://gitlab.com/openflexure/pi-gen/-/jobs/801886395

[jtc42]

Worth noting that running poetry config experimental.new-installer false beforehand fixes this for me.

[pederpansen]

@naveen521kk As it turns out, the poetry version installed via Homebrew uses a hardcoded Homebrew-installed Python 3.9. The maintainers do not seem to see any issues with that: https://github.com/Homebrew/homebrew-core/issues/53169

I think this restricts the functionality of poetry in an unacceptable way. Solution: Use the official installer.

brew uninstall poetry
curl -sSL https://raw.githubusercontent.com/python-poetry/poetry/master/get-poetry.py | python -