Add lots of Github Actions CI jobs to check sanity #2

	---
	name: Build and test
	on:
	pull_request:
	paths:
	- .github/workflows/build-and-test.yml
	- '*/.rs'
	- Cargo.toml
	- Cargo.lock
	workflow_dispatch:

	env:
	CARGO_TERM_COLOR: always
	RUSTFLAGS: --deny warnings

	jobs:
	build-and-test:
	strategy:
	matrix:
	rust: [stable, beta, nightly, 1.56.0]
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4

	- uses: actions-rs/toolchain@16499b5e05bf2e26879000db0c1d13f7e13fa3af #v1.0.7
	with:
	toolchain: ${{ matrix.rust }}
	profile: minimal
	default: true

	- name: Build
	run: cargo build --all-targets

	- name: Test
	run: cargo test

	# Make sure the library builds with all dependencies downgraded to their
	# oldest versions allowed by the semver spec. This ensures we have not
	# under-specified any dependency
	minimal-versions:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4

	- uses: actions-rs/toolchain@16499b5e05bf2e26879000db0c1d13f7e13fa3af #v1.0.7
	with:
	toolchain: nightly
	profile: minimal
	default: true

	- name: Downgrade dependencies to minimal versions
	run: cargo +nightly update -Z minimal-versions

	- name: Compile with minimal versions
	run: cargo build --all-targets

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