Bump actions/checkout from 3 to 4 #489

	name: Lint

	on: [pull_request]

	permissions: { contents: read }

	concurrency:
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: true

	jobs:
	fmt:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4

	- name: Install Rust (nightly)
	uses: actions-rust-lang/setup-rust-toolchain@v1.5.0
	with:
	toolchain: nightly
	components: rustfmt

	- name: Check with rustfmt
	run: cargo fmt --all -- --check

	clippy:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4

	- name: Install Rust
	uses: actions-rust-lang/setup-rust-toolchain@v1.5.0
	with:
	components: clippy

	- name: Check with Clippy
	run: cargo clippy --workspace --tests --all-features -- -A unknown_lints

	public-api-diff:
	runs-on: ubuntu-latest
	steps:
	- name: checkout ${{ github.base_ref }}
	uses: actions/checkout@v4
	with:
	ref: ${{ github.base_ref }}

	- name: checkout ${{ github.head_ref }}
	uses: actions/checkout@v4

	- name: Install Rust (nightly)
	uses: actions-rust-lang/setup-rust-toolchain@v1.5.0
	with:
	toolchain: nightly

	- name: Install cargo-public-api
	uses: taiki-e/cache-cargo-install-action@v1.2.1
	with:
	tool: cargo-public-api

	- name: generate API diff
	run: \|
	for f in $(find -mindepth 2 -maxdepth 2 -name Cargo.toml); do

	cargo public-api --manifest-path "$f" --all-features diff ${{ github.event.pull_request.base.sha }}..${{ github.sha }} >> /tmp/diff.txt
	done
	cat /tmp/diff.txt

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