Ensure initial positions are :across or :down

threedaymonk · Feb 9, 2014 · 2eef442 · 2eef442
1 parent 6350c79
commit 2eef442
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/lib/battleship/board.rb b/lib/battleship/board.rb
@@ -77,6 +77,7 @@ def expand_positions(positions)
     end
 
     def expand_position(x, y, length, direction)
+      raise ArgumentError unless [:across, :down].include?(direction)
       dx, dy = direction == :across ? [1, 0] : [0, 1]
       (0 ... length).map{ |i| [x + i * dx, y + i * dy] }
     end