chore(pedantic): make Clippy happy with riot-rs-arch

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

@@ -4,6 +4,7 @@ pub struct Executor;
 
 impl Executor {
     #[allow(clippy::new_without_default)]
+    #[must_use]
     pub const fn new() -> Self {
         // Actually return a value instead of marking it unimplemented like other dummy
         // functions, because this function is const and is thus run during compilation
@@ -14,6 +15,7 @@ impl Executor {
         unimplemented!();
     }
 
+    #[must_use]
     pub fn spawner(&self) -> Spawner {
         unimplemented!();
     }

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

@@ -7,14 +7,17 @@ macro_rules! define_input_like {
         }
 
         impl $type<'_> {
+            #[must_use]
             pub fn is_high(&self) -> bool {
                 unimplemented!();
             }
 
+            #[must_use]
             pub fn is_low(&self) -> bool {
                 unimplemented!();
             }
 
+            #[must_use]
             pub fn get_level(&self) -> crate::gpio::input::Level {
                 unimplemented!();
             }

src/riot-rs-arch/src/dummy/i2c/controller.rs

@@ -30,14 +30,17 @@ pub enum Frequency {
 }
 
 impl Frequency {
+    #[must_use]
     pub const fn first() -> Self {
         Self::_100k
     }
 
+    #[must_use]
     pub const fn last() -> Self {
         Self::_400k
     }
 
+    #[must_use]
     pub const fn next(self) -> Option<Self> {
         match self {
             Self::_100k => Some(Self::_400k),
@@ -46,6 +49,7 @@ impl Frequency {
         }
     }
 
+    #[must_use]
     pub const fn prev(self) -> Option<Self> {
         match self {
             Self::_100k => None,
@@ -54,6 +58,7 @@ impl Frequency {
         }
     }
 
+    #[must_use]
     pub const fn khz(self) -> u32 {
         match self {
             Self::_100k => 100,

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

@@ -2,6 +2,20 @@
 // TODO: redirect to the manufacturer-specific crate documentation when we publish it, and
 // mark every item in this dummy module `doc(hidden)`
 
+#![allow(
+    clippy::missing_errors_doc,
+    reason = "this module's items are hidden in the docs"
+)]
+#![expect(clippy::duplicated_attributes, reason = "Clippy bug #13355")]
+#![allow(
+    clippy::module_name_repetitions,
+    reason = "this dummy module mimics manufacturer-specific crates"
+)]
+#![allow(
+    clippy::needless_pass_by_value,
+    reason = "this dummy module mimics manufacturer-specific crates"
+)]
+
 mod executor;
 pub mod gpio;
 
@@ -46,6 +60,7 @@ impl From<Peripherals> for OptionalPeripherals {
     }
 }
 
+#[must_use]
 pub fn init() -> OptionalPeripherals {
     unimplemented!();
 }

src/riot-rs-arch/src/lib.rs

@@ -1,6 +1,7 @@
 //! This module dispatches between the riot-rs architecture support crates.
 
 #![no_std]
+#![deny(clippy::pedantic)]
 
 cfg_if::cfg_if! {
     if #[cfg(context = "nrf")] {