Support disabling C extensions via `IMMUTABLES_EXT=0` #200

	name: Tests

	on:
	push:
	branches:
	- master
	- ci
	pull_request:
	branches:
	- master

	jobs:
	tests:
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	python-version: ["3.8", "3.9", "3.10", "3.11", "3.12.0-beta.4"]
	os: [windows-latest, ubuntu-latest, macos-latest]
	arch: [x64, x86]
	exclude:
	# 32-bit Python is only available on Windows
	- os: ubuntu-latest
	arch: x86
	- os: macos-latest
	arch: x86

	steps:
	- uses: actions/checkout@v3
	with:
	fetch-depth: 50
	submodules: true

	- name: Check if release PR.
	uses: edgedb/action-release/validate-pr@master
	id: release
	with:
	github_token: ${{ secrets.RELEASE_BOT_GITHUB_TOKEN }}
	missing_version_ok: yes
	version_file: immutables/_version.py
	version_line_pattern: \|
	__version__\s=\s(?:['"])([[:PEP440:]])(?:['"])

	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	if: steps.release.outputs.version == 0
	env:
	PIP_DISABLE_PIP_VERSION_CHECK: 1
	with:
	python-version: ${{ matrix.python-version }}
	architecture: ${{ matrix.arch }}

	- name: Test
	if: steps.release.outputs.version == 0
	run: \|
	python -m pip install -U pip setuptools
	python -m pip install --verbose -e .[test]
	flake8 immutables/ tests/
	mypy immutables/
	python -m pytest -v

	# This job exists solely to act as the test job aggregate to be
	# targeted by branch policies.
	test-conclusion:
	name: "Test Conclusion"
	needs: [tests]
	runs-on: ubuntu-latest
	steps:
	- run: echo OK

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