Queen moves

lib/chess/moves.ex

@@ -4,6 +4,7 @@ defmodule Chess.Moves do
   alias Chess.Moves.Pawn
   alias Chess.Moves.Rook
   alias Chess.Moves.Bishop
+  alias Chess.Moves.Queen
 
   def available(board, {file, rank}) do
     piece = board["#{file},#{rank}"]
@@ -20,7 +21,7 @@ defmodule Chess.Moves do
       %{"type" => "king"} ->
         []
       %{"type" => "queen"} ->
-        []
+        Queen.moves(board, {file, rank})
     end
   end
 end

lib/chess/moves/queen.ex

@@ -0,0 +1,11 @@
+defmodule Chess.Moves.Queen do
+  @moduledoc false
+
+  alias Chess.Moves.Rook
+  alias Chess.Moves.Bishop
+
+  def moves(board, {file, rank}) do
+    Rook.moves(board, {file, rank}) ++
+      Bishop.moves(board, {file, rank})
+  end
+end

test/chess/moves/queen_test.exs

@@ -0,0 +1,24 @@
+defmodule Chess.Moves.QueenTest do
+  use Chess.DataCase
+
+  alias Chess.Moves.Queen
+
+  test "queens can move in any direction" do
+    board = %{"4,5" => %{"type" => "rook", "colour" => "white"}}
+    moves = Queen.moves(board, {4, 5})
+
+    expected_moves = Enum.sort([
+      {4, 0}, {4, 1}, {4, 2}, {4, 3}, {4, 4}, {4, 6}, {4, 7},
+      {0, 5}, {1, 5}, {2, 5}, {3, 5}, {5, 5}, {6, 5}, {7, 5},
+      {5, 6}, {6, 7},
+      {5, 4}, {6, 3}, {7, 2},
+      {3, 4}, {2, 3}, {1, 2}, {0, 1},
+      {3, 6}, {2, 7},
+    ])
+    assert Enum.sort(moves) == expected_moves
+  end
+
+  def board do
+    Chess.Board.default
+  end
+end