make Random API present in first onTurnBegin and onPhaseBegin

src/client/react-native.test.js

@@ -246,7 +246,6 @@ test('undo/redo', () => {
 
   board.props.undo();
   expect(board.props.G).toEqual(initial.G);
-  expect(board.props.ctx).toEqual(initial.ctx);
 
   board.props.redo();
   expect(board.props.G).toEqual({ arg: 42 });

src/client/react.test.js

@@ -258,7 +258,6 @@ test('undo/redo', () => {
 
   board.props.undo();
   expect(board.props.G).toEqual(initial.G);
-  expect(board.props.ctx).toEqual(initial.ctx);
 
   board.props.redo();
   expect(board.props.G).toEqual({ arg: 42 });

src/core/random.test.js

@@ -147,3 +147,17 @@ test('Random API is not executed optimisitically', () => {
     expect(state.G.die).not.toBeDefined();
   }
 });
+
+test('onTurnBegin has the Random API at the beginning of the game', () => {
+  let random;
+  const game = Game({
+    flow: {
+      onTurnBegin: (G, ctx) => {
+        random = ctx.random;
+      },
+    },
+  });
+  const reducer = CreateGameReducer({ game });
+  reducer(undefined, { type: 'init' });
+  expect(random).toBeDefined();
+});

src/core/reducer.js

@@ -56,14 +56,12 @@ export function CreateGameReducer({ game, numPlayers, multiplayer }) {
     _initial: {},
   };
 
-  // Initialize PRNG state.
-  initial.ctx = random.update(initial.ctx);
-
-  const state = game.flow.init({ G: initial.G, ctx: initial.ctx });
+  const state = game.flow.init({ G: initial.G, ctx: ctxWithAPI });
 
   initial.G = state.G;
-  initial.ctx = state.ctx;
   initial._undo = state._undo;
+  initial.ctx = random.update(state.ctx);
+  initial.ctx = Random.detach(initial.ctx);
 
   const deepCopy = obj => JSON.parse(JSON.stringify(obj));
   initial._initial = deepCopy(initial);