Refactor using Clippy nursery and unwrap_used

src/game.rs

@@ -4,25 +4,25 @@ use crate::{
 };
 use String as FenError;
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
 pub struct Game {
     pub board: Board,
     pub state: State,
 }
 
 impl Game {
-    pub fn new() -> Game {
-        Game {
+    pub const fn new() -> Self {
+        Self {
             board: Board::new(),
             state: State::new(),
         }
     }
 
-    pub fn new_from_fen(fen: &str) -> Result<Game, FenError> {
+    pub fn new_from_fen(fen: &str) -> Result<Self, FenError> {
         from_fen(fen)
     }
 
-    pub fn run(&self) {
+    pub const fn run(&self) {
         Board::new();
     }
 }
@@ -33,7 +33,7 @@ impl Default for Game {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
 pub struct State {
     side_to_move: Color,
     castling_ability: u8,
@@ -43,8 +43,8 @@ pub struct State {
 }
 
 impl State {
-    pub fn new() -> State {
-        State {
+    pub const fn new() -> Self {
+        Self {
             side_to_move: Color::White,
             castling_ability: 0b1111,
             en_passant_target_square: 0,
@@ -53,14 +53,14 @@ impl State {
         }
     }
 
-    pub fn load_state(
+    pub const fn load_state(
         side_to_move: Color,
         castling_ability: u8,
         en_passant_target_square: u8,
         halfmove_clock: u8,
         fullmove_counter: u8,
-    ) -> State {
-        State {
+    ) -> Self {
+        Self {
             side_to_move,
             castling_ability,
             en_passant_target_square,