Improve copy performance.

docs/README.md

@@ -6,7 +6,6 @@
 |--------|-------------|
 | [**Board**](#Board) |  |
 | [Board::__construct](#Board__construct) | Load piece placement or setup initial position. |
-| [Board::copy](#Boardcopy) | Creates deep copy of the board instance. |
 | [Board::__toString](#Board__toString) |  |
 | [Board::export](#Boardexport) | Export piece placement string. |
 | [Board::preview](#Boardpreview) | Preview of the board in ASCII graphics. |
@@ -24,7 +23,7 @@
 | [Board::is_check](#Boardis_check) | Tells whether the king of color specified is in check. |
 | [**FEN**](#FEN) | FEN is a standard notation for describing a particular board position of a chess game |
 | [FEN::__construct](#FEN__construct) | Load FEN or setup starting position. |
-| [FEN::copy](#FENcopy) | Creates deep copy of the FEN instance. |
+| [FEN::__clone](#FEN__clone) |  |
 | [FEN::export](#FENexport) | Export whole FEN string. |
 | [FEN::export_short](#FENexport_short) | Export FEN string without halfmoves count and fullmove number. |
 | [FEN::__toString](#FEN__toString) |  |
@@ -146,25 +145,6 @@ digits 1 through 8 (the number of empty squares), and "/" separates ranks.
 
 
 
----
-### Board::copy
-
-Creates deep copy of the board instance.
-
-```php
-Board::copy(  ): mixed
-```
-
-
-
-
-
-**Return Value:**
-
-
-
-
-
 ---
 ### Board::__toString
 
@@ -582,12 +562,12 @@ FEN::__construct( string fen = 'rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQ
 
 
 ---
-### FEN::copy
+### FEN::__clone
+
 
-Creates deep copy of the FEN instance.
 
 ```php
-FEN::copy(  ): mixed
+FEN::__clone(  ): mixed
 ```
 
 

src/Board.php

@@ -28,14 +28,6 @@ function __construct(string $pieces = 'rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKB
     }
   }
 
-  /**
-  * Creates deep copy of the board instance.
-  */
-  public function copy()
-  {
-    return new self($this->export());
-  }
-
   private function split_to_ranks(string $pieces) : array
   {
     $pieces = preg_replace('/\s+/', '', $pieces);

src/FEN.php

@@ -45,13 +45,11 @@ function __construct(string $fen = 'rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR
       $this->set_fullmove($parts[5] ?? 1);
     }
 
-    /**
-    * Creates deep copy of the FEN instance.
-    */
-    public function copy()
-    {
-      return new self($this->export());
-    }
+    public function __clone()
+  	{
+  		$this->board = clone $this->board;
+      $this->en_passant = clone $this->en_passant;
+  	}
 
     /**
     * Export whole FEN string.
@@ -541,7 +539,7 @@ public function get_legal_moves() : array
     */
     public function is_legal_move(string $move) : bool
     {
-      $fen = $this->copy();
+      $fen = clone $this;
       try {
         $fen->move($move);
       } catch (\Exception $e) {
@@ -575,7 +573,7 @@ private function castle_kingside(Move &$move) : void
         throw new RulesException("Castling not available. King in check.");
       }
 
-      $new_board = $this->board->copy();
+      $new_board = clone $this->board;
       $new_board->set_square($origin, '');
       $new_board->set_square($origin->get_relative_square(1, 0), $this->get_active_piece('K'));
       if ($new_board->is_check($this->get_active_color())) {
@@ -615,7 +613,7 @@ private function castle_queenside(Move &$move) : void
         throw new RulesException("Castling not available. King in check.");
       }
 
-      $new_board = $this->board->copy();
+      $new_board = clone $this->board;
       $new_board->set_square($origin, '');
       $new_board->set_square($origin->get_relative_square(-1, 0), $this->get_active_piece('K'));
       if ($new_board->is_check($this->get_active_color())) {
@@ -734,7 +732,7 @@ private function standard_move(Move &$move) : void
 
     private function get_new_board(Move $move, Square $origin) : Board
     {
-      $new_board = $this->board->copy();
+      $new_board = clone $this->board;
       $piece = $this->get_active_piece($move->get_piece_type());
       $target = $move->get_target(true);
 

src/PGN.php

@@ -155,7 +155,7 @@ public function get_tags() : array
   public function get_initial_fen(bool $as_object = false)
   {
     if ($as_object) {
-      return $this->initial_fen->copy();
+      return clone $this->initial_fen;
     }
     return $this->initial_fen->export();
   }
@@ -196,7 +196,7 @@ public function get_fen_after_halfmove(int $halfmove_number, bool $as_object = f
     }
     $fen = $this->fens[$halfmove_index];
     if ($as_object) {
-      return $fen->copy();
+      return clone $fen;
     }
     return $fen->export();
   }
@@ -223,7 +223,7 @@ private function get_last_computed_fen() : FEN
     if ($computed == 0) {
       return $this->get_initial_fen(true);
     }
-    return $this->fens[$computed - 1]->copy();
+    return clone $this->fens[$computed - 1];
   }
 
   private function compute_fens(int $max_halfmove_to_compute) : void
@@ -239,7 +239,7 @@ private function compute_fens(int $max_halfmove_to_compute) : void
       } catch (\Exception $e) {
         throw new \Exception('Move ' . ceil($halfmove_number / 2) . ($halfmove_number % 2 ? '. ' : '... ') . $halfmove . ' is invalid. FEN ' . $this->get_fen_after_halfmove($halfmove_number - 1), 0, $e);
       }
-      $this->fens[] = $fen->copy();
+      $this->fens[] = clone $fen;
     }
   }
 

tests/benchmark/BoardBench.php

@@ -0,0 +1,24 @@
+<?php
+namespace Onspli\Chess;
+
+class BoardBench
+{
+
+  /**
+  * @Revs(10)
+  */
+  public function benchConstructor()
+  {
+    $board = new Board('rnbqkbnr/pp1ppppp/8/2p5/4P3/8/PPPP1PPP/RNBQKBNR');
+  }
+
+  /**
+  * @Revs(10)
+  */
+  public function benchCopy()
+  {
+    $board = new Board('rnbqkbnr/pp1ppppp/8/2p5/4P3/8/PPPP1PPP/RNBQKBNR');
+    $board2 = clone $board;
+  }
+
+}

tests/benchmark/FENBench.php

@@ -24,7 +24,7 @@ public function benchConstructor()
   public function benchCopy()
   {
     $fen = new FEN('rnbqkbnr/pp1ppppp/8/2p5/4P3/8/PPPP1PPP/RNBQKBNR b KQq c6 1 2');
-    $fen->copy();
+    $fen2 = clone $fen;
   }
 
   /**

tests/unit/BoardTest.php

@@ -173,7 +173,7 @@ public function testIsSquareVacant() : void
   public function testCopy() : void
   {
     $board1 = new Board('rnbqkbnr/pp1ppppp/8/2p5/4P3/8/PPPP1PPP/RNBQKBNR');
-    $board2 = $board1->copy();
+    $board2 = clone $board1;
 
     $this->assertEquals($board1->export(), $board2->export());
     $board2->set_square('a1', '');

tests/unit/FENTest.php

@@ -17,11 +17,13 @@ public function testStringable() : void
   public function testCopy() : void
   {
     $fen = new FEN;
-    $fen2 = $fen->copy();
+    $fen2 = clone $fen;
     $fen->set_square('e4', 'Q');
     $fen->set_fullmove(5);
+    $fen->set_en_passant('e3');
     $this->assertEquals('', $fen2->get_square('e4'));
     $this->assertEquals(1, $fen2->get_fullmove());
+    $this->assertEquals('-', $fen2->get_en_passant());
   }
 
   public function testSetFullmoveInvalid1() : void