def disambiguate_pawns(possibilities)
      self.move.piece.match(/p/i) && !self.move.capture ?
        possibilities.reject {|p| self.board.position_for(p).match(/2|7/) } :
        possibilities
    end
def disambiguate_pawns(possibilities)
      self.move.piece.match(/p/i) && !self.move.capture ?
        possibilities.reject {|p| self.board.position_for(p).match(/2|7/) } :
        possibilities
    end
A pawn can't move two spaces if there is a pawn in front of it.