Merge pull request #535 from KodrAus/chore/housekeeping

Make more things const

src/lib.rs

@@ -307,7 +307,7 @@ impl Uuid {
     /// Currently only the RFC4122 variant is generated by this module.
     ///
     /// * [Variant Reference](http://tools.ietf.org/html/rfc4122#section-4.1.1)
-    pub fn get_variant(&self) -> Option<Variant> {
+    pub const fn get_variant(&self) -> Option<Variant> {
         match self.as_bytes()[8] {
             x if x & 0x80 == 0x00 => Some(Variant::NCS),
             x if x & 0xc0 == 0x80 => Some(Variant::RFC4122),
@@ -335,7 +335,7 @@ impl Uuid {
     /// Returns the version of the UUID.
     ///
     /// This represents the algorithm used to generate the contents
-    pub fn get_version(&self) -> Option<Version> {
+    pub const fn get_version(&self) -> Option<Version> {
         let v = self.as_bytes()[6] >> 4;
         match v {
             0 if self.is_nil() => Some(Version::Nil),
@@ -392,19 +392,21 @@ impl Uuid {
     /// }
     /// ```
     pub fn as_fields(&self) -> (u32, u16, u16, &[u8; 8]) {
-        let d1 = u32::from(self.as_bytes()[0]) << 24
-            | u32::from(self.as_bytes()[1]) << 16
-            | u32::from(self.as_bytes()[2]) << 8
-            | u32::from(self.as_bytes()[3]);
+        let bytes = self.as_bytes();
+
+        let d1 = (bytes[0] as u32) << 24
+            | (bytes[1] as u32) << 16
+            | (bytes[2] as u32) << 8
+            | (bytes[3] as u32);
 
         let d2 =
-            u16::from(self.as_bytes()[4]) << 8 | u16::from(self.as_bytes()[5]);
+            (bytes[4] as u16) << 8 | (bytes[5] as u16);
 
         let d3 =
-            u16::from(self.as_bytes()[6]) << 8 | u16::from(self.as_bytes()[7]);
+            (bytes[6] as u16) << 8 | (bytes[7] as u16);
 
         let d4: &[u8; 8] =
-            convert::TryInto::try_into(&self.as_bytes()[8..16]).unwrap();
+            convert::TryInto::try_into(&bytes[8..16]).unwrap();
         (d1, d2, d3, d4)
     }
 
@@ -435,16 +437,16 @@ impl Uuid {
     /// }
     /// ```
     pub fn to_fields_le(&self) -> (u32, u16, u16, &[u8; 8]) {
-        let d1 = u32::from(self.as_bytes()[0])
-            | u32::from(self.as_bytes()[1]) << 8
-            | u32::from(self.as_bytes()[2]) << 16
-            | u32::from(self.as_bytes()[3]) << 24;
+        let d1 = (self.as_bytes()[0] as u32)
+            | (self.as_bytes()[1] as u32) << 8
+            | (self.as_bytes()[2] as u32) << 16
+            | (self.as_bytes()[3] as u32) << 24;
 
         let d2 =
-            u16::from(self.as_bytes()[4]) | u16::from(self.as_bytes()[5]) << 8;
+            (self.as_bytes()[4] as u16) | (self.as_bytes()[5] as u16) << 8;
 
         let d3 =
-            u16::from(self.as_bytes()[6]) | u16::from(self.as_bytes()[7]) << 8;
+            (self.as_bytes()[6] as u16) | (self.as_bytes()[7] as u16) << 8;
 
         let d4: &[u8; 8] =
             convert::TryInto::try_into(&self.as_bytes()[8..16]).unwrap();
@@ -470,23 +472,23 @@ impl Uuid {
     ///     Ok(())
     /// }
     /// ```
-    pub fn as_u128(&self) -> u128 {
-        u128::from(self.as_bytes()[0]) << 120
-            | u128::from(self.as_bytes()[1]) << 112
-            | u128::from(self.as_bytes()[2]) << 104
-            | u128::from(self.as_bytes()[3]) << 96
-            | u128::from(self.as_bytes()[4]) << 88
-            | u128::from(self.as_bytes()[5]) << 80
-            | u128::from(self.as_bytes()[6]) << 72
-            | u128::from(self.as_bytes()[7]) << 64
-            | u128::from(self.as_bytes()[8]) << 56
-            | u128::from(self.as_bytes()[9]) << 48
-            | u128::from(self.as_bytes()[10]) << 40
-            | u128::from(self.as_bytes()[11]) << 32
-            | u128::from(self.as_bytes()[12]) << 24
-            | u128::from(self.as_bytes()[13]) << 16
-            | u128::from(self.as_bytes()[14]) << 8
-            | u128::from(self.as_bytes()[15])
+    pub const fn as_u128(&self) -> u128 {
+        (self.as_bytes()[0] as u128) << 120
+            | (self.as_bytes()[1] as u128) << 112
+            | (self.as_bytes()[2] as u128) << 104
+            | (self.as_bytes()[3] as u128) << 96
+            | (self.as_bytes()[4] as u128) << 88
+            | (self.as_bytes()[5] as u128) << 80
+            | (self.as_bytes()[6] as u128) << 72
+            | (self.as_bytes()[7] as u128) << 64
+            | (self.as_bytes()[8] as u128) << 56
+            | (self.as_bytes()[9] as u128) << 48
+            | (self.as_bytes()[10] as u128) << 40
+            | (self.as_bytes()[11] as u128) << 32
+            | (self.as_bytes()[12] as u128) << 24
+            | (self.as_bytes()[13] as u128) << 16
+            | (self.as_bytes()[14] as u128) << 8
+            | (self.as_bytes()[15] as u128)
     }
 
     /// Returns a 128bit little-endian value containing the UUID data.
@@ -515,23 +517,23 @@ impl Uuid {
     ///     Ok(())
     /// }
     /// ```
-    pub fn to_u128_le(&self) -> u128 {
-        u128::from(self.as_bytes()[0])
-            | u128::from(self.as_bytes()[1]) << 8
-            | u128::from(self.as_bytes()[2]) << 16
-            | u128::from(self.as_bytes()[3]) << 24
-            | u128::from(self.as_bytes()[4]) << 32
-            | u128::from(self.as_bytes()[5]) << 40
-            | u128::from(self.as_bytes()[6]) << 48
-            | u128::from(self.as_bytes()[7]) << 56
-            | u128::from(self.as_bytes()[8]) << 64
-            | u128::from(self.as_bytes()[9]) << 72
-            | u128::from(self.as_bytes()[10]) << 80
-            | u128::from(self.as_bytes()[11]) << 88
-            | u128::from(self.as_bytes()[12]) << 96
-            | u128::from(self.as_bytes()[13]) << 104
-            | u128::from(self.as_bytes()[14]) << 112
-            | u128::from(self.as_bytes()[15]) << 120
+    pub const fn to_u128_le(&self) -> u128 {
+        (self.as_bytes()[0] as u128)
+            | (self.as_bytes()[1] as u128) << 8
+            | (self.as_bytes()[2] as u128) << 16
+            | (self.as_bytes()[3] as u128) << 24
+            | (self.as_bytes()[4] as u128) << 32
+            | (self.as_bytes()[5] as u128) << 40
+            | (self.as_bytes()[6] as u128) << 48
+            | (self.as_bytes()[7] as u128) << 56
+            | (self.as_bytes()[8] as u128) << 64
+            | (self.as_bytes()[9] as u128) << 72
+            | (self.as_bytes()[10] as u128) << 80
+            | (self.as_bytes()[11] as u128) << 88
+            | (self.as_bytes()[12] as u128) << 96
+            | (self.as_bytes()[13] as u128) << 104
+            | (self.as_bytes()[14] as u128) << 112
+            | (self.as_bytes()[15] as u128) << 120
     }
 
     /// Returns two 64bit values containing the UUID data.
@@ -555,7 +557,7 @@ impl Uuid {
     ///     Ok(())
     /// }
     /// ```
-    pub fn as_u64_pair(&self) -> (u64, u64) {
+    pub const fn as_u64_pair(&self) -> (u64, u64) {
         let value = self.as_u128();
         ((value >> 64) as u64, value as u64)
     }
@@ -566,8 +568,8 @@ impl Uuid {
     }
 
     /// Tests if the UUID is nil.
-    pub fn is_nil(&self) -> bool {
-        self.as_bytes().iter().all(|&b| b == 0)
+    pub const fn is_nil(&self) -> bool {
+        self.as_u128() == 0
     }
 
     /// A buffer that can be used for `encode_...` calls, that is