Enforce usage of const fn more aggresively

src/devices/korg_kaoss_dj/output.rs

@@ -24,7 +24,7 @@ use crate::{
 const LED_OFF: u8 = 0x00;
 const LED_ON: u8 = 0x7f;
 
-fn led_to_u7(output: LedOutput) -> u8 {
+const fn led_to_u7(output: LedOutput) -> u8 {
     match output {
         LedOutput::Off => LED_OFF,
         LedOutput::On => LED_ON,
@@ -148,7 +148,7 @@ impl TryFrom<ControlIndex> for Led {
 }
 
 #[must_use]
-pub fn led_output_into_midi_message(led: Led, output: LedOutput) -> [u8; 3] {
+pub const fn led_output_into_midi_message(led: Led, output: LedOutput) -> [u8; 3] {
     let (status, data1) = match led {
         Led::Main(led) => match led {
             MainLed::TabButton => (MIDI_STATUS_BUTTON_MAIN, MIDI_TAP_BUTTON),

src/devices/ni_traktor_kontrol_s4mk3/mod.rs

@@ -250,7 +250,7 @@ impl DeviceContext {
     }
 
     #[must_use]
-    pub fn info(&self) -> &DeviceInfo {
+    pub const fn info(&self) -> &DeviceInfo {
         &self.info
     }
 

src/devices/pioneer_ddj_400/input.rs

@@ -127,7 +127,7 @@ impl PerformancePadSensor {
             Self::KeyShift(nr) => nr + 0x70,
         }
     }
-    fn try_from_u8(pad_id: u8) -> Option<Self> {
+    const fn try_from_u8(pad_id: u8) -> Option<Self> {
         let sensor = match pad_id {
             0x00..=0x07 => Self::HotCue(pad_id),
             0x10..=0x17 => Self::PadFx1(pad_id - 0x10),

src/hid/mod.rs

@@ -262,20 +262,20 @@ impl<'a> TryFrom<&'a DeviceInfo> for DeviceId<'a> {
 
 impl HidDevice {
     #[must_use]
-    pub fn new(info: DeviceInfo) -> Self {
+    pub const fn new(info: DeviceInfo) -> Self {
         Self {
             info,
             connected: None,
         }
     }
 
     #[must_use]
-    pub fn info(&self) -> &DeviceInfo {
+    pub const fn info(&self) -> &DeviceInfo {
         &self.info
     }
 
     #[must_use]
-    pub fn is_connected(&self) -> bool {
+    pub const fn is_connected(&self) -> bool {
         self.connected.is_some()
     }
 

src/input/mod.rs

@@ -475,7 +475,7 @@ pub trait ControlInputEventSink {
 
 #[must_use]
 pub fn split_crossfader_input_linear(input: CenterSliderInput) -> (SliderInput, SliderInput) {
-    fn f_x(x: f32) -> f32 {
+    const fn f_x(x: f32) -> f32 {
         x
     }
     let CenterSliderInput { position } = input;

src/lib.rs

@@ -13,6 +13,7 @@
 #![warn(clippy::pedantic)]
 // Additional restrictions
 #![warn(clippy::clone_on_ref_ptr)]
+#![warn(clippy::missing_const_for_fn)]
 #![warn(clippy::self_named_module_files)]
 // Repetitions of module/type names occur frequently when using many
 // modules for keeping the size of the source files handy. Often

src/midi/midir.rs

@@ -73,7 +73,7 @@ where
     I: MidiInputGateway + Send,
 {
     #[must_use]
-    fn new(
+    const fn new(
         descriptor: MidiDeviceDescriptor,
         input_port: MidirInputPort,
         output_port: MidirOutputPort,
@@ -87,17 +87,17 @@ where
     }
 
     #[must_use]
-    pub fn descriptor(&self) -> &MidiDeviceDescriptor {
+    pub const fn descriptor(&self) -> &MidiDeviceDescriptor {
         &self.descriptor
     }
 
     #[must_use]
-    pub fn input_port(&self) -> &MidirInputPort {
+    pub const fn input_port(&self) -> &MidirInputPort {
         &self.input_port
     }
 
     #[must_use]
-    pub fn output_port(&self) -> &MidirOutputPort {
+    pub const fn output_port(&self) -> &MidirOutputPort {
         &self.output_port
     }
 
@@ -119,7 +119,7 @@ where
     }
 
     #[must_use]
-    pub fn is_connected(&self) -> bool {
+    pub const fn is_connected(&self) -> bool {
         self.input_connection.is_some()
     }
 

src/param/atomic.rs

@@ -114,7 +114,7 @@ impl AtomicValue {
     }
 
     #[must_use]
-    pub fn value_type(&self) -> ValueType {
+    pub const fn value_type(&self) -> ValueType {
         match self {
             Self::Bool(_) => ValueType::Bool,
             Self::I32(_) => ValueType::I32,

src/param/ramping.rs

@@ -54,7 +54,7 @@ fn steps_as_f32(steps: usize) -> f32 {
 impl RampingF32 {
     /// Create an immediate value without interpolation
     #[must_use]
-    pub fn new(value: f32) -> Self {
+    pub const fn new(value: f32) -> Self {
         Self {
             profile: RampingProfile::immediate(),
             initial_value: value,
@@ -106,7 +106,7 @@ impl RampingF32 {
     }
 
     #[must_use]
-    pub fn target_value(&self) -> f32 {
+    pub const fn target_value(&self) -> f32 {
         self.target_value
     }