Refactor code based on clippy suggestions

src/bytes_base64.rs

@@ -6,7 +6,31 @@ pub struct BytesBase64(pub Vec<u8>);
 
 impl std::fmt::Display for BytesBase64 {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "Base64({})", self.to_string())
+        let BytesBase64(digits) = self;
+        let mut r: Vec<u8> = digits
+            .iter()
+            .map(|d| match d {
+                0..=25 => *d + b'A',
+                26..=51 => *d - 26 + b'a',
+                52..=61 => *d - 52 + b'0',
+                62 => b'+',
+                63 => b'/',
+                _ => panic!("Unexpected base64 digit '{}'", d),
+            })
+            .collect();
+        // Handle padding
+        let pad = b'=';
+        match r.len() % 4 {
+            0 => (),
+            2 => {
+                r.push(pad);
+                r.push(pad);
+            }
+            3 => r.push(pad),
+            _ => panic!("Unexpected lenght for padding '{}'", r.len()),
+        }
+        let s = str::from_utf8(r.as_slice()).unwrap().to_string();
+        write!(f, "{}", s)
     }
 }
 
@@ -22,7 +46,7 @@ impl BytesBase64 {
                 (v[0] & 0b11111100) >> 2,
                 (v[0] & 0b00000011) << 4 | (v[1] & 0b11110000) >> 4,
                 (v[1] & 0b00001111) << 2 | (v[2] & 0b11000000) >> 6,
-                (v[2] & 0b00111111) << 0,
+                (v[2] & 0b00111111),
             ];
             // removed padded bytes
             for _ in c.len()..3 {
@@ -30,7 +54,7 @@ impl BytesBase64 {
             }
             result
         }
-        BytesBase64(bytes.chunks(3).map(|c| to_base64(c)).flatten().collect())
+        BytesBase64(bytes.chunks(3).flat_map(to_base64).collect())
     }
 
     pub fn to_bytes(&self) -> Bytes {
@@ -44,7 +68,7 @@ impl BytesBase64 {
             let mut result: Vec<u8> = vec![
                 ((v[0] & 0b00111111) << 2) | ((v[1] & 0b00110000) >> 4),
                 ((v[1] & 0b00001111) << 4) | ((v[2] & 0b00111100) >> 2),
-                ((v[2] & 0b00000011) << 6) | ((v[3] & 0b00111111) >> 0),
+                ((v[2] & 0b00000011) << 6) | (v[3] & 0b00111111),
             ];
             // removed padded bytes
             for _ in c.len()..4 {
@@ -52,16 +76,16 @@ impl BytesBase64 {
             }
             result
         }
-        Bytes(v.chunks(4).map(|c| to_bytes(c)).flatten().collect())
+        Bytes(v.chunks(4).flat_map(to_bytes).collect())
     }
 
     pub fn from_base64(s: &str) -> Result<BytesBase64, String> {
         let mut r: Vec<u8> = Vec::with_capacity(s.len());
         for c in s.chars() {
             match c {
-                'A'..='Z' => r.push((c as u8) - ('A' as u8)),
-                'a'..='z' => r.push((c as u8) - ('a' as u8) + 26),
-                '0'..='9' => r.push((c as u8) - ('0' as u8) + 52),
+                'A'..='Z' => r.push((c as u8) - b'A'),
+                'a'..='z' => r.push((c as u8) - b'a' + 26),
+                '0'..='9' => r.push((c as u8) - b'0' + 52),
                 '+' => r.push(62),
                 '/' => r.push(63),
                 '\n' => (),
@@ -74,31 +98,4 @@ impl BytesBase64 {
         }
         Ok(BytesBase64(r))
     }
-
-    pub fn to_string(&self) -> String {
-        let BytesBase64(digits) = self;
-        let mut r: Vec<u8> = digits
-            .iter()
-            .map(|d| match d {
-                0..=25 => *d + ('A' as u8),
-                26..=51 => *d - 26 + ('a' as u8),
-                52..=61 => *d - 52 + ('0' as u8),
-                62 => '+' as u8,
-                63 => '/' as u8,
-                _ => panic!("Unexpected base64 digit '{}'", d),
-            })
-            .collect();
-        // Handle padding
-        let pad = '=' as u8;
-        match r.len() % 4 {
-            0 => (),
-            2 => {
-                r.push(pad);
-                r.push(pad);
-            }
-            3 => r.push(pad),
-            _ => panic!("Unexpected lenght for padding '{}'", r.len()),
-        }
-        str::from_utf8(r.as_slice()).unwrap().to_string()
-    }
 }