HOW ON EARTH AM I SUPPOSED TO THROW AN ERROW AND CONTINUE THE DAMN CODE DUE TO KO RULE, HUH????

closing as this particular behavior is indeed mentionned

These color games this kata is doing is just driving me insane, I can't actually understand which one is black and which one is white. It is so unclear. And another thing that appears to me to be strange is : Why is black making the first move? Shouldn't it be white?

There are practical reasons, why some Go software has rollbacks. It gives the player the possibility to analyse their game play on the computer, just like on a real Go board: Taking back a number of moves and try a different variation to see if the outcome is better than the original (main) variation of the game. Also you can save game records with the real game as main variation and show some side variations, including comments why this variation is better and that is worse. This is usually done by stronger Go players and is replayed by weaker Go players using Go software capable reading these game records. There is a notation protocol (the GTP protocol) , which most common Go software use to read and write Go game records.

As explained above, not a kata issue.

This shouldn't be an issue. It is stated in the Kata's description in section "Placing stones on board":
"Note that the letter I is omitted from possible coordinates."

There are pracitcal reasons for it. In live tournament Go games the players may need to write down their game records to be able to recreate the game unaltered in case some issues came up at the end, for example while scoring the final game state. Beside graphical notation on preprinted empty go board sheets it is possible to record the game in simple text form (similar to chess). This is done by writing down who's turn it is and where that player's stone was placed, for example "Bh4 Wc3 Bd16" and so on. To avoid confusing i and j there is no i column in the Go board coordinates.

Be careful when specifying the alphabet for the columns, because the letter "i" is omitted in the tests :)

Check the details section:
"For calculating the average point you may add your point to the given array!"
To my understanding that adding yourPoints is optional

The description says that you can:
"
rollback
User should be able to rollback a set amount of turns on the go board.
"
Accordingly, the rollback method takes one argument - the number of steps back. Which means to return the state of the board n moves back. This means that every movement on the board must preserve the previous state of the board in order to return to it if necessary.
For example, after movements for board 9x9, the result will be a board:

moves = "7A", "1A"
board = '''
  A B C D E F G H J
9 . . . . . . . . .
8 . . . . . . . . .
7 x . . . . . . . .
6 . . . . . . . . .
5 . . . . . . . . .
4 . . . . . . . . .
3 . . . . . . . . .
2 . . . . . . . . .
1 o . . . . . . . .
'''

If the rollback method with argument 2 is called, the result will be a starting board:

board = '''
  A B C D E F G H J
9 . . . . . . . . .
8 . . . . . . . . .
7 . . . . . . . . .
6 . . . . . . . . .
5 . . . . . . . . .
4 . . . . . . . . .
3 . . . . . . . . .
2 . . . . . . . . .
1 . . . . . . . . .
'''

I hope this clears something up?
p.s. Initially did not specify, I will add, that together with the rollback of the board, rollback should also be made for the order of the players' moves.

Nonsense, the kata is fun to the point when you start encountering weird ideas that author came up with to "spice" things up. Most ridiculous of which is something called "rollback", which I have no idea how it is supposed to work and description certainly does not clarify this. It has nothing to do with the game of Go and is total nonsense. Basically I have written the whole solution but cannot get it through random tests because idk what author had in mind.

Fun challenge but the instructions needs to be rewritten. There are several requirements that are never given in the instructions. I got halfway through only to find that I should be able to handle multiple move inputs at once. This really should be mentioned in the move section, its pretty important.

Hi

A question : why testing the state of the board with game.board instead of game.board(), the same for turn

IMHO , a method or function gives more freedom to implentation (it's encapsulation in fact) ,

Accessing directly to attributes creates a constraint : it fixes the type of attributes and /or implies permanent updating of them

This kata's description is ridiculously badly written. It is so frustrating to write the whole solution just to find out at the end that there is supposed to be a rollback functionality. The self capture move is not explained, some edge cases are not explained, important information does not get highlighted enough (letter I does not count etc.). This kata would be pretty fun to complete if not for this terrible explanation...

This kata should be updated from Node 10.x. It is one of the very last ( less than 20, realistically less than 10 ) to prevent removal of that Node version.