Add Nix builds for the full registry #1767

	name: tests

	on:
	push:
	branches: [master]
	pull_request:

	jobs:
	tests:
	runs-on: ubuntu-latest
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	SPACES_KEY: ${{ secrets.SPACES_KEY }}
	SPACES_SECRET: ${{ secrets.SPACES_SECRET }}
	steps:
	# Setup
	- name: Check out source repository
	uses: actions/checkout@v2

	- name: Install Nix
	uses: DeterminateSystems/nix-installer-action@v4
	with:
	github-token: ${{ env.GITHUB_TOKEN }}

	- name: Setup Nix cache
	uses: DeterminateSystems/magic-nix-cache-action@v2

	# Separates all the cache downloading time from the time required to actually run a step
	# of the workflow
	- name: Initialize Nix
	run: nix develop

	# First we build the two packages that represent the build outputs of the
	# registry for general consumers
	- name: Build the registry server
	run: nix build .#server

	- name: Build the registry GitHub importer
	run: nix build .#github-importer

	# Then we run the flake checks, which will build all packages and scripts
	# in the registry, and will also run tests and check formatting.
	- name: Run flake checks
	run: nix flake check

	# Unfortunately I can't run 'spago test' in a derivation because it doesn't
	# have a mode that ignores the cache
	- name: Run Spago tests
	run: nix develop --command run-tests-script

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