New shared builds mechanism (mockup) #625

	name: CI self+toolchain
	# Build Alire with `alr build` and using a toolchain installed from Alire
	# The `alr` being tested is the one which is being submitted in the PR

	on:
	pull_request:
	paths-ignore:
	- 'doc/**'
	- '**.md'
	- '**.rst'
	- '**.txt'

	jobs:

	build:

	name: ${{ matrix.os }}

	runs-on: ${{ matrix.os }}

	strategy:
	matrix:
	os:
	- macos-latest
	- ubuntu-latest
	- windows-latest

	steps:
	- name: Check out
	uses: actions/checkout@v3
	with:
	submodules: true

	# Use a stock alr to make the latest toolchain available

	- name: Install FSF toolchain
	uses: alire-project/alr-install@v1
	with:
	crates: gnat_native gprbuild

	- name: Build alr with default toolchain
	shell: bash
	run: dev/build.sh

	# We can start using the alr we just built

	- name: Update dependencies
	run: ./bin/alr -n update

	- name: Show dependencies/pins
	run: ./bin/alr -n -q with --solve \|\| ./bin/alr -n -v -d with --solve

	- name: Show build environment
	run: ./bin/alr -n printenv

	- shell: bash
	run: mv ./bin ./bin-old
	# Windows doesn't allow to replace a running exe so the next command fails otherwise

	- name: SELF-BUILD
	run: ./bin-old/alr -n build

	- name: Show built version
	run: ./bin/alr -n version

	# Run the testsuite with the just build alr. The testsuite picks the proper
	# alr in the ./bin/alr location.

	- name: Install Python 3.x # required by testsuite
	uses: actions/setup-python@v2
	with:
	python-version: '3.x'

	- name: Install e3
	run: pip install --upgrade e3-testsuite

	- name: Run testsuite
	run: cd testsuite; ./run.py -E
	shell: bash

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