Read Box<[u8]> in bulk instead of byte by byte

azalea-buf/src/impls/extra.rs

@@ -148,6 +148,17 @@ impl AzBuf for Vec<u8> {
     }
 }
 
+impl AzBuf for Box<[u8]> {
+    fn azalea_read(buf: &mut Cursor<&[u8]>) -> Result<Self, BufReadError> {
+        let length = i32::azalea_read_var(buf)? as usize;
+        read_bytes(buf, length).map(Box::from)
+    }
+    fn azalea_write(&self, buf: &mut impl Write) -> io::Result<()> {
+        (self.len() as u32).azalea_write_var(buf)?;
+        buf.write_all(self)
+    }
+}
+
 impl AzBuf for String {
     fn azalea_read(buf: &mut Cursor<&[u8]>) -> Result<Self, BufReadError> {
         read_utf_with_len(buf, MAX_STRING_LENGTH).map(Into::into)

azalea-buf/src/lib.rs

@@ -22,6 +22,20 @@ mod tests {
 
     use super::*;
 
+    #[test]
+    fn test_boxed_bytes() {
+        let data: Box<[u8]> = (0..=255u8).cycle().take(3000).collect();
+        let mut buf = Vec::new();
+        data.azalea_write(&mut buf).unwrap();
+
+        let mut cursor = Cursor::new(buf.as_slice());
+        assert_eq!(Box::<[u8]>::azalea_read(&mut cursor).unwrap(), data);
+        assert_eq!(cursor.position(), buf.len() as u64);
+
+        let truncated = &buf[..buf.len() - 1];
+        assert!(Box::<[u8]>::azalea_read(&mut Cursor::new(truncated)).is_err());
+    }
+
     #[test]
     fn test_write_varint() {
         let mut buf = Vec::new();