Add some specs for parsing SAN

spec/lx_chess/game/parse_san_spec.cr

@@ -0,0 +1,34 @@
+require "../../spec_helper"
+require "../../../src/lx_chess/board"
+require "../../../src/lx_chess/piece"
+require "../../../src/lx_chess/move_set"
+require "../../../src/lx_chess/game"
+
+include LxChess
+
+describe Game do
+  describe "#parse_san" do
+    context "when SAN is a pawn move" do
+      it "returns a correct from and to square" do
+        game = Game.new
+        game.board["e2"] = Piece.from_fen('P')
+        from, to = game.parse_san("e4")
+        from.should eq(game.board.index("e2"))
+        to.should eq(game.board.index("e4"))
+      end
+
+      it "disambiguates the move correctly" do
+        game = Game.new
+        place(game.board, {
+          "d4" => 'P',
+          "f4" => 'P',
+          "e5" => 'p',
+        })
+
+        moves = game.parse_san("dxe5")
+        debug_board(game, moves)
+        moves.should eq(["d4", "e5"].map { |s| game.board.index(s) })
+      end
+    end
+  end
+end

spec/spec_helper.cr

@@ -19,6 +19,6 @@ end
 
 def place(board : LxChess::Board, squares : Hash(String, Char))
   squares.each do |cord, sym|
-    game.board[cord] = LxChess::Piece.from_fen(sym)
+    board[cord] = LxChess::Piece.from_fen(sym)
   end
 end

src/lx_chess.cr

@@ -44,6 +44,7 @@ player_white = LxChess::Player.new
 player_black = LxChess::Player.new
 game = LxChess::Game.new(board: fen.board, players: [player_white, player_black])
 gb = LxChess::TermBoard.new(game.board)
+
 if theme = options["theme"]?
   if LxChess::TermBoard::THEMES[theme]?
     gb.board_theme = theme

src/lx_chess/game.cr

@@ -44,6 +44,7 @@ module LxChess
       (@move_clock / 2).to_i16
     end
 
+    # Return the current player's king
     def own_king
       @board.find do |piece|
         next unless piece
@@ -51,6 +52,11 @@ module LxChess
       end
     end
 
+    # Parse SAN from a string
+    def parse_san(notation : String)
+      parse_san(Notation.new(notation))
+    end
+
     # Parse standard algebraic notation
     def parse_san(notation : Notation)
       index = @board.index(notation.square)