Weird behavior when returning string from `order.first()`

[janKir]

I misunderstood the instructions on how to use the custom order functions and returned the playerID (a string) instead of the playOrder index (a number) from a phase's order.first() function.

const phase = {
  moves: { ... },
  turn: {
    order: {
      first: (G) => G.firstPlayer
    }
  }
}

This also worked for the first move, and the correct player was set. This made it hard to detect where the upcoming unexpected behavior originated: When ending the first turn (and also phase), the second player was not the next player in playOrder as expected, but (in a 4 player game) was always either player "1" if the first player was player "0" or "2" or player "3" if the first player was player "1" or "3".

Despite the question why the app behaved like this, I would suggest making misuse of the first() function more clear or allow returning a string playerID with expected behavior.

[nicolodavis]

I agree. We should probably log an error for cases like this.

[sarlow]

Thanks for bringing this up - I ran into the same issue as well. The unexpected behavior you mentioned comes from the way that the next player is calculated:

next: (G, ctx) => (ctx.playOrderPos + 1) % ctx.numPlayers

If playOrderPos is set to a string (e.g. "2"), then for a 4-player game:

next: (G, ctx) => ("2"+ 1) % 4
next: (G, ctx) => (21) % 4
next: (G, ctx) => 1

I agree that an error message (or an additional note in the documentation) would be helpful.