ci: merge queue and registry caching #67

	name: PR
	on:
	pull_request:

	jobs:

	test:
	name: Test
	runs-on: ubuntu-latest
	strategy:
	matrix:
	rust: [1.31.0, stable]
	steps:
	- uses: actions/checkout@v3
	- uses: actions/cache@v4
	if: startsWith(matrix.rust, '1')
	with:
	path: ~/.cargo/registry/index
	key: cargo-${{ matrix.rust }}-git-index
	- uses: dtolnay/rust-toolchain@master
	with:
	toolchain: ${{ matrix.rust }}
	- run: cargo build
	- run: ./ci/test_full.sh

	fmt:
	name: Format
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3
	- uses: dtolnay/rust-toolchain@1.62.0
	with:
	components: rustfmt
	- run: cargo fmt --all --check

	# One job that "summarizes" the success state of this pipeline. This can then be added to branch
	# protection, rather than having to add each job separately.
	success:
	name: Success
	runs-on: ubuntu-latest
	needs: [test, fmt]
	# Github branch protection is exceedingly silly and treats "jobs skipped because a dependency
	# failed" as success. So we have to do some contortions to ensure the job fails if any of its
	# dependencies fails.
	if: always() # make sure this is never "skipped"
	steps:
	# Manually check the status of all dependencies. `if: failure()` does not work.
	- name: check if any dependency failed
	run: jq --exit-status 'all(.result == "success")' <<< '${{ toJson(needs) }}'

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