Add board tests

test/chess/board_test.exs

@@ -0,0 +1,43 @@
+defmodule Chess.BoardTest do
+  @moduledoc false
+
+  use Chess.DataCase
+
+  alias Chess.Board
+
+  test "returns a piece from the board" do
+    board = Board.default
+
+    expected_piece = %{"type" => "pawn", "colour" => "white"}
+    assert Board.piece(board, {4, 1}) == expected_piece
+  end
+
+  test "finds pieces on the board" do
+    board = Board.default
+
+    piece = %{"type" => "pawn", "colour" => "white"}
+    expected_result = [
+      {0, 1}, {1, 1}, {2, 1}, {3, 1}, {4, 1}, {5, 1}, {6, 1}, {7, 1},
+    ]
+    assert Board.search(board, piece) == expected_result
+  end
+
+  test "finds a single piece on the board" do
+    board = Board.default
+
+    piece = %{"type" => "king", "colour" => "black"}
+    assert Board.search(board, piece) == [{4, 7}]
+  end
+
+  test "moves a piece" do
+    board = %{
+      "3,0" => %{"type" => "queen",  "colour" => "white"},
+    }
+
+    new_board = Board.move_piece(board, %{"from" => [3, 0], "to" => [5, 2]})
+
+    assert new_board == %{
+      "5,2" => %{"type" => "queen",  "colour" => "white"},
+    }
+  end
+end