fix(core): Don’t error if turn.order.next returns undefined (#614)

* fix(core): Don’t error if turn.next returns undefined

* fix(core): Mention in `turn.order.next` error that undefined is OK

Author: delucis

src/core/turn-order.ts

@@ -289,9 +289,9 @@ export function UpdateTurnOrderState(
   } else {
     const t = order.next(G, ctx);
     const type = typeof t;
-    if (type !== 'number') {
+    if (t !== undefined && type !== 'number') {
       logging.error(
-        `invalid value returned by turn.order.next — expected number got ${type} “${t}”.`
+        `invalid value returned by turn.order.next — expected number or undefined, got ${type} “${t}”.`
       );
     }
 

src/types.ts

@@ -159,7 +159,7 @@ export interface StageMap {
 
 export interface TurnOrderConfig {
   first: (G: any, ctx: Ctx) => number;
-  next: (G: any, ctx: Ctx) => number;
+  next: (G: any, ctx: Ctx) => number | undefined;
   playOrder?: (G: any, ctx: Ctx) => PlayerID[];
 }