From ec7dde5404310c8c948416d2eed3c8ed6edc1ce0 Mon Sep 17 00:00:00 2001
From: Dean Scarff <dos@scarff.id.au>
Date: Sat, 30 Mar 2019 00:44:05 +1100
Subject: [PATCH] Don't leak undefined ctx properties from
 turnOrder.actionPlayers (#382)

- Removes _actionPlayersOthers because it is never read
- Defaults _actionPlayersOnce to false rather than undefined

Fixes nicolodavis/boardgame.io#381
---
 src/core/turn-order.js      |  3 +--
 src/core/turn-order.test.js | 39 +++++++++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/src/core/turn-order.js b/src/core/turn-order.js
index 6550a4414..de0379ba7 100644
--- a/src/core/turn-order.js
+++ b/src/core/turn-order.js
@@ -70,8 +70,7 @@ function setActionPlayers(G, ctx, arg) {
   return {
     ...ctx,
     actionPlayers,
-    _actionPlayersOnce: arg.once,
-    _actionPlayersOthers: arg.others,
+    _actionPlayersOnce: arg.once || false,
   };
 }
 
diff --git a/src/core/turn-order.test.js b/src/core/turn-order.test.js
index 11d8c4150..eb6c171a7 100644
--- a/src/core/turn-order.test.js
+++ b/src/core/turn-order.test.js
@@ -13,6 +13,29 @@ import { makeMove, gameEvent } from './action-creators';
 import { InitializeGame, CreateGameReducer } from './reducer';
 
 describe('turnOrder', () => {
+  // Defines a matcher for testing that ctx has no undefined properties.
+  // Identifies which property is undefined.
+  expect.extend({
+    toHaveUndefinedProperties(ctx) {
+      const undefinedEntry = Object.entries(ctx).find(entry => {
+        const [, value] = entry;
+        return value === undefined;
+      });
+      if (undefinedEntry === undefined) {
+        return {
+          message: () => `expected some properties of ctx to be undefined`,
+          pass: false,
+        };
+      } else {
+        const [k] = undefinedEntry;
+        return {
+          message: () => `expected ctx.${k} to be defined`,
+          pass: true,
+        };
+      }
+    },
+  });
+
   test('DEFAULT', () => {
     const flow = FlowWithPhases({
       startingPhase: 'A',
@@ -23,6 +46,8 @@ describe('turnOrder', () => {
     state = flow.init(state);
     expect(state.ctx.currentPlayer).toBe('0');
     expect(state.ctx.actionPlayers).toEqual(['0']);
+    expect(state.ctx).not.toHaveUndefinedProperties();
+
     state = flow.processGameEvent(state, gameEvent('endTurn'));
     expect(state.ctx.currentPlayer).toBe('1');
     expect(state.ctx.actionPlayers).toEqual(['1']);
@@ -43,6 +68,8 @@ describe('turnOrder', () => {
     state = flow.init(state);
     expect(state.ctx.currentPlayer).toBe('0');
     expect(state.ctx.actionPlayers).toEqual(['0']);
+    expect(state.ctx).not.toHaveUndefinedProperties();
+
     state = flow.processGameEvent(state, gameEvent('endTurn'));
     expect(state.ctx.currentPlayer).toBe('1');
     expect(state.ctx.actionPlayers).toEqual(['1']);
@@ -61,6 +88,8 @@ describe('turnOrder', () => {
     state = flow.init(state);
     expect(state.ctx.currentPlayer).toBe('0');
     expect(state.ctx.actionPlayers).toEqual(['0', '1']);
+    expect(state.ctx).not.toHaveUndefinedProperties();
+
     state = flow.processGameEvent(state, gameEvent('endTurn'));
     expect(state.ctx.currentPlayer).toBe('0');
     expect(state.ctx.actionPlayers).toEqual(['0', '1']);
@@ -79,6 +108,7 @@ describe('turnOrder', () => {
     expect(state.ctx.phase).toBe('A');
     expect(state.ctx.currentPlayer).toBe('0');
     expect(state.ctx.actionPlayers).toEqual(['0', '1']);
+    expect(state.ctx).not.toHaveUndefinedProperties();
 
     state = flow.processGameEvent(state, gameEvent('endTurn'));
 
@@ -108,6 +138,8 @@ describe('turnOrder', () => {
     state = flow.init(state);
     expect(state.ctx.currentPlayer).toBe('0');
     expect(state.ctx.actionPlayers).toEqual(['1', '2']);
+    expect(state.ctx).not.toHaveUndefinedProperties();
+
     state = flow.processGameEvent(state, gameEvent('endTurn'));
     expect(state.ctx.currentPlayer).toBe('0');
     expect(state.ctx.actionPlayers).toEqual(['1', '2']);
@@ -126,6 +158,7 @@ describe('turnOrder', () => {
     expect(state.ctx.phase).toBe('A');
     expect(state.ctx.currentPlayer).toBe('0');
     expect(state.ctx.actionPlayers).toEqual(['1', '2']);
+    expect(state.ctx).not.toHaveUndefinedProperties();
 
     state = flow.processGameEvent(state, gameEvent('endTurn'));
 
@@ -155,6 +188,8 @@ describe('turnOrder', () => {
     state = flow.init(state);
 
     expect(state.ctx.currentPlayer).toBe('1');
+    expect(state.ctx).not.toHaveUndefinedProperties();
+
     state = flow.processGameEvent(state, gameEvent('endTurn'));
     expect(state.ctx.currentPlayer).toBe('0');
   });
@@ -168,6 +203,8 @@ describe('turnOrder', () => {
     state = flow.init(state);
 
     expect(state.ctx.currentPlayer).toBe('2');
+    expect(state.ctx).not.toHaveUndefinedProperties();
+
     state = flow.processGameEvent(state, gameEvent('endTurn'));
     expect(state.ctx.currentPlayer).toBe('1');
     state = flow.processGameEvent(state, gameEvent('endTurn'));
@@ -184,6 +221,8 @@ describe('turnOrder', () => {
     state = flow.init(state);
     expect(state.ctx.currentPlayer).toBe('9');
     expect(state.ctx.actionPlayers).toEqual(['9']);
+    expect(state.ctx).not.toHaveUndefinedProperties();
+
     state = flow.processGameEvent(state, gameEvent('endTurn'));
     expect(state.ctx.currentPlayer).toBe('3');
     expect(state.ctx.actionPlayers).toEqual(['3']);