Added U14 primitive value type

Author: sourcebox

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Added
 
 - `Message` enum variants for *System Common* and *System Realtime* messages.
+- `U14` primitive value type.
 - Derive `Debug`, `Clone`, `Eq`, and `PartialEq` for `U4`.
 - Derive `Debug`, `Clone`, `Eq`, and `PartialEq` for `InvalidU4`.
 - Derive `Debug`, `Clone`, `Eq`, and `PartialEq` for `InvalidU7`.

src/message/data/mod.rs

@@ -1,5 +1,6 @@
 //! Primitives and structures used in USB MIDI data.
 
+pub mod u14;
 pub mod u4;
 pub mod u7;
 

src/message/data/u14.rs

@@ -0,0 +1,78 @@
+//! A primitive value with 14-bit length.
+
+use crate::message::data::{FromClamped, FromOverFlow};
+
+/// A primitive value that can be from 0-0x4000
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct U14(u16);
+
+/// Error representing that this value is not a valid u14
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct InvalidU14(pub u16);
+
+impl TryFrom<u16> for U14 {
+    type Error = InvalidU14;
+
+    fn try_from(value: u16) -> Result<Self, Self::Error> {
+        if value > 0x3FFF {
+            Err(InvalidU14(value))
+        } else {
+            Ok(U14(value))
+        }
+    }
+}
+
+impl From<U14> for u16 {
+    fn from(value: U14) -> u16 {
+        value.0
+    }
+}
+
+impl FromOverFlow<u16> for U14 {
+    fn from_overflow(value: u16) -> U14 {
+        const MASK: u16 = 0b0011_1111_1111_1111;
+        let value = MASK & value;
+        U14(value)
+    }
+}
+
+impl FromClamped<u16> for U14 {
+    fn from_clamped(value: u16) -> U14 {
+        match U14::try_from(value) {
+            Ok(x) => x,
+            _ => U14::MAX,
+        }
+    }
+}
+
+impl U14 {
+    /// Maximum value for the type.
+    pub const MAX: U14 = U14(0x3FFF);
+    /// Minimum value for the type.
+    pub const MIN: U14 = U14(0);
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn try_from_valid() {
+        assert_eq!(U14::try_from(0x1234), Ok(U14(0x1234)));
+    }
+
+    #[test]
+    fn try_from_invalid() {
+        assert_eq!(U14::try_from(0x4000), Err(InvalidU14(0x4000)));
+    }
+
+    #[test]
+    fn from_overflow() {
+        assert_eq!(U14::from_overflow(0x400F), U14(0x0F));
+    }
+
+    #[test]
+    fn from_clamped() {
+        assert_eq!(U14::from_clamped(0x400F), U14(0x3FFF));
+    }
+}