impl Arbitrary for fundamental types

Cargo.toml

@@ -17,6 +17,7 @@ alloc = []
 std = ["alloc", "btoi/std", "nohash-hasher?/std"]
 variant = []
 nohash-hasher = ["dep:nohash-hasher"]
+arbitrary = ["dep:arbitrary"]
 
 [[bench]]
 name = "benches"
@@ -30,6 +31,7 @@ bitflags = "2.0.0"
 btoi = { version = "0.4", default-features = false }
 arrayvec = { version = "0.7", default-features = false }
 nohash-hasher = { version = "0.2", default-features = false, optional = true }
+arbitrary = { version = "1.3.2", optional = true, features = ["derive"] }
 
 [dev-dependencies]
 csv = "1.3"

src/bitboard.rs

@@ -23,6 +23,7 @@ use crate::square::{File, Rank, Square};
 /// // . 1 . . . 1 . .
 /// ```
 #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Default)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 pub struct Bitboard(pub u64);
 
 impl Bitboard {

src/castling_side.rs

@@ -7,6 +7,7 @@ use crate::{
 
 /// `KingSide` (O-O) or `QueenSide` (O-O-O).
 #[derive(Copy, Clone, Eq, PartialEq, Debug, Hash)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 pub enum CastlingSide {
     KingSide,
     QueenSide,
@@ -101,6 +102,7 @@ impl ops::BitXorAssign<bool> for CastlingSide {
 
 /// Container with values for each [`CastlingSide`].
 #[derive(Copy, Clone, Default, Eq, PartialEq, Debug, Hash)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 #[repr(C)]
 pub struct ByCastlingSide<T> {
     pub king_side: T,

src/color.rs

@@ -12,6 +12,7 @@ use crate::{
 /// `White` or `Black`.
 #[allow(missing_docs)]
 #[derive(Copy, Clone, Eq, PartialEq, Debug, Hash)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 pub enum Color {
     Black = 0,
     White = 1,
@@ -213,6 +214,7 @@ try_color_from_int_impl! { u8 i8 u16 i16 u32 i32 u64 i64 u128 i128 usize isize }
 
 /// Container with values for each [`Color`].
 #[derive(Copy, Clone, Default, Eq, PartialEq, Debug, Hash)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 pub struct ByColor<T> {
     pub black: T,
     pub white: T,

src/role.rs

@@ -15,6 +15,7 @@ use crate::{color::Color, types::Piece, util::out_of_range_error};
 /// ```
 #[allow(missing_docs)]
 #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Debug, Hash)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 pub enum Role {
     Pawn = 1,
     Knight = 2,
@@ -161,6 +162,7 @@ try_role_from_int_impl! { u8 i8 u16 i16 u32 i32 u64 i64 u128 i128 usize isize }
 
 /// Container with values for each [`Role`].
 #[derive(Copy, Clone, Default, Eq, PartialEq, Debug, Hash)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 #[repr(C)]
 pub struct ByRole<T> {
     pub pawn: T,

src/square.rs

@@ -30,6 +30,7 @@ macro_rules! try_from_int_impl {
 /// A file of the chessboard.
 #[allow(missing_docs)]
 #[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 #[repr(u8)]
 pub enum File {
     A = 0,
@@ -151,6 +152,7 @@ try_from_int_impl! { File, 0, 8, u8 i8 u16 i16 u32 i32 u64 i64 u128 i128 usize i
 /// A rank of the chessboard.
 #[allow(missing_docs)]
 #[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 #[repr(u8)]
 pub enum Rank {
     First = 0,
@@ -281,6 +283,7 @@ impl std::error::Error for ParseSquareError {}
 #[rustfmt::skip]
 #[allow(missing_docs)]
 #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 #[repr(u8)]
 pub enum Square {
     A1 = 0, B1, C1, D1, E1, F1, G1, H1,

src/types.rs

@@ -14,6 +14,7 @@ use crate::{
 /// A piece with [`Color`] and [`Role`].
 #[allow(missing_docs)]
 #[derive(Copy, Clone, Eq, PartialEq, Debug, Hash)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 pub struct Piece {
     pub color: Color,
     pub role: Role,

src/variant.rs

@@ -17,6 +17,7 @@ use crate::{
 
 /// Discriminant of [`VariantPosition`].
 #[derive(Debug, Eq, PartialEq, Hash, Clone, Copy, Default)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 pub enum Variant {
     /// See [`Chess`].
     #[default]

src/zobrist.rs

@@ -44,10 +44,11 @@ pub trait ZobristValue: BitXorAssign + Default + Copy {
 
 macro_rules! zobrist_value_impl {
     ($t:ident, $proxy:ty, $bits:literal) => {
-        #[derive(Default, Copy, Clone, Eq)]
         #[doc = "A [`ZobristValue`] with "]
         #[doc = stringify!($bits)]
         #[doc = " bits."]
+        #[derive(Default, Copy, Clone, Eq)]
+        #[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
         pub struct $t(pub $proxy);
 
         impl PartialEq for $t {