ci: integrate clippy

.github/workflows/main.yml

@@ -10,7 +10,7 @@ on:
   merge_group:
 
 jobs:
-  CI:
+  build:
     runs-on: ubuntu-latest
 
     env:
@@ -58,14 +58,34 @@ jobs:
 
         laze build --partition hash:${{ matrix.partition }} --builders microbit-v2,nrf52840dk,rpi-pico,rpi-pico-w -g
 
+  lint:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Check out repository code
+      uses: actions/checkout@v4
+
+    - name: Install toolchain
+      uses: dtolnay/rust-toolchain@nightly
+      with:
+        components: clippy
+
+    - name: rust cache
+      uses: Swatinem/rust-cache@v2
+
+    # TODO: we'll eventually want to check the whole workspace with --workspace
+    # TODO: we'll eventually want to check relevant feature combinations
+    # TODO: we may want to use --no-deps as well
+    - run: cargo clippy --verbose --locked -p riot-rs-embassy
+
   CI-success:
       if: ${{ always() }}
       runs-on: ubuntu-latest
       name: Final Results
-      needs: [CI]
+      needs: [build]
       steps:
         - run: |
-            result="${{ needs.CI.result }}"
+            result="${{ needs.build.result }}"
             if [[ $result == "success" || $result == "skipped" ]]; then
               exit 0
             else

src/riot-rs-embassy/src/arch/dummy.rs

@@ -3,8 +3,18 @@
 /// Dummy type.
 ///
 /// See the `OptionalPeripherals` type of your Embassy architecture crate instead.
+#[derive(Default)]
 pub struct OptionalPeripherals;
 
+/// Dummy type.
+pub struct Peripherals;
+
+impl From<Peripherals> for OptionalPeripherals {
+    fn from(_peripherals: Peripherals) -> Self {
+        Self {}
+    }
+}
+
 mod executor {
     use embassy_executor::SpawnToken;
 
@@ -25,15 +35,16 @@ mod executor {
     pub struct Spawner {}
 
     impl Spawner {
-        pub fn spawn<S>(&self, token: SpawnToken<S>) -> Result<(), ()> {
+        #[allow(clippy::result_unit_err)]
+        pub fn spawn<S>(&self, _token: SpawnToken<S>) -> Result<(), ()> {
             Ok(())
         }
     }
 }
 pub use executor::{Executor, Spawner};
 
-pub fn init(_: ()) -> OptionalPeripherals {
-    OptionalPeripherals {}
+pub fn init(_: OptionalPeripherals) -> Peripherals {
+    Peripherals {}
 }
 
 pub struct SWI;

src/riot-rs-rt/src/lib.rs

@@ -31,7 +31,7 @@ cfg_if::cfg_if! {
     else {
         mod arch {
             pub fn init() {}
-            pub fn benchmark<F: Fn() -> ()>(_iterations: usize, f: F) -> core::result::Result<usize, ()> {
+            pub fn benchmark<F: Fn()>(_iterations: usize, _f: F) -> core::result::Result<usize, ()> {
                 unimplemented!();
             }
         }

src/riot-rs-rt/src/testing.rs

@@ -5,7 +5,7 @@
 use super::debug;
 
 pub trait Testable {
-    fn run(&self) -> ();
+    fn run(&self);
 }
 
 impl<T> Testable for T