Refactor using Clippy nursery and unwrap_used

src/board.rs

@@ -1,15 +1,15 @@
 use std::fmt;
 use u64 as Bitboard;
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
 pub struct Board {
     white_pieces: [Piece; 6],
     black_pieces: [Piece; 6],
 }
 
 impl Board {
-    pub fn new() -> Board {
-        Board {
+    pub const fn new() -> Self {
+        Self {
             white_pieces: [
                 Piece::new(0xff00, Kind::Pawn, Color::White),
                 Piece::new(0x81, Kind::Rook, Color::White),
@@ -29,8 +29,8 @@ impl Board {
         }
     }
 
-    pub fn empty_board() -> Board {
-        Board {
+    pub const fn empty_board() -> Self {
+        Self {
             white_pieces: [
                 Piece::new(0x0, Kind::Pawn, Color::White),
                 Piece::new(0x0, Kind::Rook, Color::White),
@@ -85,7 +85,7 @@ impl fmt::Display for Board {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
 pub struct Piece {
     pub bitboard: Bitboard,
     pub kind: Kind,
@@ -93,8 +93,8 @@ pub struct Piece {
 }
 
 impl Piece {
-    pub fn new(bitboard: Bitboard, kind: Kind, color: Color) -> Piece {
-        Piece {
+    pub const fn new(bitboard: Bitboard, kind: Kind, color: Color) -> Self {
+        Self {
             bitboard,
             kind,
             color,
@@ -116,7 +116,7 @@ impl fmt::Display for Piece {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
 pub enum Kind {
     Pawn,
     Rook,
@@ -126,7 +126,7 @@ pub enum Kind {
     King,
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
 pub enum Color {
     White,
     Black,