add clippy and formatting to ci

Author: PgBiel

.github/workflows/ci.yml

@@ -1,11 +1,28 @@
 name: Continuous integration
 on: [push, pull_request]
 
+env:
+  RUSTFLAGS: "-Dwarnings"
+  RUSTDOCFLAGS: "-Dwarnings"
+
 jobs:
-  ci:
+  test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
       - run: cargo build
       - run: cargo test
+
+  checks:
+    name: Check clippy, formatting, and documentation
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@1.81.0
+        with:
+          components: clippy, rustfmt
+      - uses: Swatinem/rust-cache@v2
+      - run: cargo clippy --workspace --all-targets --all-features
+      - run: cargo fmt --check --all
+      - run: cargo doc --workspace --no-deps