chore: fix clippy warnings (#270)

Author: koushiro

examples/custom_table.rs

@@ -34,9 +34,9 @@ fn main() {
     // Create new hashes from some input data. This is done through the `Code` enum we derived
     // Multihash from.
     let blake_hash = Code::Blake2b200.digest(b"hello world!");
-    println!("{:02x?}", blake_hash);
+    println!("{blake_hash:02x?}");
     let truncated_sha2_hash = Code::Sha2_256Truncated20.digest(b"hello world!");
-    println!("{:02x?}", truncated_sha2_hash);
+    println!("{truncated_sha2_hash:02x?}");
 
     // Sometimes you might not need to hash new data, you just want to get the information about
     // a Multihash.

examples/manual_mh.rs

@@ -14,9 +14,9 @@ fn prefix_util() {
 
     let code_hex = hex::encode(&empty[..1]); // change if longer/shorter prefix
     let len_hex = hex::encode(len);
-    println!("prefix hex: code: {}, len: {}", code_hex, len_hex);
+    println!("prefix hex: code: {code_hex}, len: {len_hex}");
 
-    println!("{}{}{}", code_hex, len_hex, hash);
+    println!("{code_hex}{len_hex}{hash}");
 }
 
 fn main() {

src/error.rs

@@ -23,10 +23,10 @@ pub enum Error {
 impl core::fmt::Display for Error {
     fn fmt(&self, f: &mut core::fmt::Formatter) -> core::fmt::Result {
         match self {
-            Self::Io(err) => write!(f, "{}", err),
-            Self::UnsupportedCode(code) => write!(f, "Unsupported multihash code {}.", code),
-            Self::InvalidSize(size) => write!(f, "Invalid multihash size {}.", size),
-            Self::Varint(err) => write!(f, "{}", err),
+            Self::Io(err) => write!(f, "{err}"),
+            Self::UnsupportedCode(code) => write!(f, "Unsupported multihash code {code}."),
+            Self::InvalidSize(size) => write!(f, "Invalid multihash size {size}."),
+            Self::Varint(err) => write!(f, "{err}"),
         }
     }
 }

src/multihash.rs

@@ -238,7 +238,10 @@ impl<const S: usize> Multihash<S> {
     ///
     /// let hash = Code::Sha3_256.digest(b"Hello world!");
     /// let (.., arr, size) = hash.into_inner();
-    /// let foo = Foo { arr, len: size as usize };
+    /// let foo = Foo {
+    ///     arr,
+    ///     len: size as usize,
+    /// };
     /// ```
     pub fn into_inner(self) -> (u64, [u8; S], u8) {
         let Self { code, digest, size } = self;

tests/lib.rs

@@ -231,7 +231,7 @@ where
     H: Hasher + Default,
 {
     let digest = hex::decode(digest_str).unwrap();
-    let expected_bytes = hex::decode(format!("{}{}", prefix, digest_str)).unwrap();
+    let expected_bytes = hex::decode(format!("{prefix}{digest_str}")).unwrap();
     let mut expected_cursor = Cursor::new(&expected_bytes);
     let multihash = code.digest(b"hello world");