set default RNG seed once per game, not game type

Author: darthfiddler

src/core/game.js

@@ -7,7 +7,6 @@
  */
 
 import { FlowWithPhases } from './flow';
-import { Random } from './random';
 
 /**
  * Game
@@ -76,7 +75,6 @@ function Game({ name, setup, moves, playerView, flow, seed }) {
   if (setup === undefined) setup = () => ({});
   if (moves === undefined) moves = {};
   if (playerView === undefined) playerView = G => G;
-  if (seed === undefined) seed = Random.seed();
 
   if (!flow || flow.processGameEvent === undefined) {
     flow = FlowWithPhases(flow || {});

src/core/random.test.js

@@ -148,16 +148,21 @@ test('Random API is not executed optimisitically', () => {
   }
 });
 
-test('onTurnBegin has the Random API at the beginning of the game', () => {
-  let random;
+test('onTurnBegin has ctx APIs at the beginning of the game', () => {
+  let random = null;
+  let events = null;
+
   const game = Game({
     flow: {
       onTurnBegin: (G, ctx) => {
         random = ctx.random;
+        events = ctx.events;
       },
     },
   });
+
   const reducer = CreateGameReducer({ game });
   reducer(undefined, { type: 'init' });
-  expect(random).toBeDefined();
+  expect(random).not.toBe(null);
+  expect(events).not.toBe(null);
 });

src/core/reducer.js

@@ -24,7 +24,12 @@ export function CreateGameReducer({ game, numPlayers, multiplayer }) {
   }
 
   let ctx = game.flow.ctx(numPlayers);
-  ctx._random = { seed: game.seed };
+
+  let seed = game.seed;
+  if (seed === undefined) {
+    seed = Random.seed();
+  }
+  ctx._random = { seed };
 
   const random = new Random(ctx);
   let ctxWithAPI = random.attach(ctx);

src/core/reducer.test.js

@@ -205,7 +205,7 @@ test('log', () => {
   expect(state.log).toEqual([actionA, actionB, actionC]);
 });
 
-test('using Random inside setup()', () => {
+describe('Random inside setup()', () => {
   const game1 = Game({
     seed: 'seed1',
     setup: ctx => ({ n: ctx.random.D6() }),
@@ -221,17 +221,29 @@ test('using Random inside setup()', () => {
     setup: ctx => ({ n: ctx.random.D6() }),
   });
 
-  const reducer1 = CreateGameReducer({ game: game1 });
-  const state1 = reducer1(undefined, makeMove());
+  const game4 = Game({
+    setup: ctx => ({ n: ctx.random.D6() }),
+  });
+
+  test('setting seed', () => {
+    const reducer1 = CreateGameReducer({ game: game1 });
+    const state1 = reducer1(undefined, makeMove());
 
-  const reducer2 = CreateGameReducer({ game: game2 });
-  const state2 = reducer2(undefined, makeMove());
+    const reducer2 = CreateGameReducer({ game: game2 });
+    const state2 = reducer2(undefined, makeMove());
 
-  const reducer3 = CreateGameReducer({ game: game3 });
-  const state3 = reducer3(undefined, makeMove());
+    const reducer3 = CreateGameReducer({ game: game3 });
+    const state3 = reducer3(undefined, makeMove());
 
-  expect(state1.G.n).not.toBe(state2.G.n);
-  expect(state2.G.n).toBe(state3.G.n);
+    expect(state1.G.n).not.toBe(state2.G.n);
+    expect(state2.G.n).toBe(state3.G.n);
+  });
+
+  test('not setting seed sets a default', () => {
+    const reducer = CreateGameReducer({ game: game4 });
+    const state = reducer(undefined, makeMove());
+    expect(state.ctx._random.seed).toBeDefined();
+  });
 });
 
 test('undo / redo', () => {