getCellsToFlip: function getCellsToFlip(board, lastRow, lastCol) {
    function searchDirection(direction, opponentsLetter) {
      let num = 0;
      let done = false;
      let resultArr = [];
      let nextRow = lastRow;
      let nextCol = lastCol;
      while (!done) {
        num += 1;
        switch (direction) {
            case "N":
              nextRow = lastRow - num;
              nextCol = lastCol;
              break;
            case "NW":
              nextRow = lastRow - num;
              nextCol = lastCol - num;
              break;
            case "W":
              nextRow = lastRow;
              nextCol = lastCol - num;
              break;
            case "SW":
              nextRow = lastRow + num;
              nextCol = lastCol - num;
              break;
            case "S":
              nextRow = lastRow + num;
              nextCol = lastCol;
              break;
            case "SE":
              nextRow = lastRow + num;
              nextCol = lastCol + num;
              break;
            case "E":
              nextRow = lastRow;
              nextCol = lastCol + num;
              break;
            case "NE":
              nextRow = lastRow - num;
              nextCol = lastCol + num;
              break;
        }
        validSpace = withinBoundaries(board, nextRow, nextCol);
        if (!validSpace) {
          return [];
        }
        nextIndex = rev.rowColToIndex(board, nextRow, nextCol);
        if (board[nextIndex] === " ") {
          return [];
        }

        if (board[nextIndex] !== opponentsLetter) {
          done = true;
        };
        if (board[nextIndex] === opponentsLetter) {
          resultArr.push([nextRow, nextCol]);
        }
      }
      return resultArr;
    }