Cirrus CI: using install_pre_requirements key again. #642

	name: Linux Wheels

	on: [push, pull_request]

	jobs:
	build_wheels:
	name: Build wheels on ${{ matrix.os }}
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	os: [ubuntu-20.04]

	steps:
	- uses: actions/checkout@v3

	- name: Build wheels
	uses: pypa/cibuildwheel@v2.15.0
	env:
	# Skip Python 32 bit Linux, and PyPy
	CIBW_SKIP: "-manylinux_i686 musllinux* pp*"
	CIBW_BEFORE_ALL_LINUX: yum install -y tk mesa-libGLU-devel
	CIBW_BEFORE_BUILD: >
	pip install cython FXrays low_index sphinx sphinx_rtd_theme &&
	pip install --pre --extra-index-url https://test.pypi.org/simple cypari &&
	pip install git+https://github.com/3-manifolds/PLink &&
	pip install git+https://github.com/3-manifolds/snappy_manifolds &&
	pip install git+https://github.com/3-manifolds/Spherogram
	CIBW_BEFORE_TEST: >
	pip install cython low_index &&
	pip install --pre --extra-index-url https://test.pypi.org/simple cypari &&
	pip install git+https://github.com/3-manifolds/PLink &&
	pip install git+https://github.com/3-manifolds/snappy_manifolds &&
	pip install git+https://github.com/3-manifolds/Spherogram
	CIBW_REPAIR_WHEEL_COMMAND_LINUX: auditwheel repair --strip -w {dest_dir} {wheel}
	CIBW_TEST_COMMAND: python -m snappy.test --skip-modern-opengl

	- uses: actions/upload-artifact@v3
	with:
	name: snappy_linux_wheels
	path: ./wheelhouse/*.whl

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