refactor: Synchronized is a mixin

TODO.md

@@ -1,7 +1,7 @@
 # TODO
 
 - ✔ Remove dependency on decorators
-- ❌ Synchronized should be a mixin
+- ✔ Synchronized should be a mixin
 - ❌ Behavior items should derive type/name
 - ✔ Precompile behavior traversals
 - ❌ Abstract physics world tick (no destructuring)

packages/entity/index.js

@@ -5,7 +5,7 @@ import without from 'lodash.without';
 import {compose} from '@avocado/core';
 import {EventEmitter} from '@avocado/mixins';
 import {Resource} from '@avocado/resource';
-import {SynchronizedMixin} from '@avocado/state';
+import {Synchronized} from '@avocado/state';
 
 import {hasTrait, lookupTrait} from './trait-registry';
 
@@ -47,7 +47,7 @@ function enumerateTraitProperties(prototype) {
 
 const decorate = compose(
   EventEmitter,
-  SynchronizedMixin,
+  Synchronized,
 );
 
 export class Entity extends decorate(Resource) {

packages/entity/list/index.js

@@ -10,9 +10,10 @@ import {Entity} from '../index';
 
 const decorate = compose(
   EventEmitter,
+  Synchronized,
 );
 
-export class EntityList extends decorate(Synchronized) {
+export class EntityList extends decorate(class {}) {
 
   constructor() {
     super();

packages/entity/trait.js

@@ -1,11 +1,16 @@
 import * as I from 'immutable';
 
+import {compose} from '@avocado/core';
 import {Vector} from '@avocado/math';
 import {Property} from '@avocado/mixins';
 import {Resource} from '@avocado/resource';
 import {Synchronized} from '@avocado/state';
 
-export class Trait extends Synchronized {
+const decorate = compose(
+  Synchronized,
+);
+
+export class Trait extends decorate(class {}) {
 
   constructor(entity, params, state) {
     super();

packages/state/index.js

@@ -2,5 +2,5 @@ export {nextStep} from './next-step';
 export {Packer, Unpacker} from './packer';
 export {StatePacket} from './packet/state.packet';
 export {StateKeysPacket} from './packet/state-keys.packet';
-export {Synchronized, SynchronizedMixin} from './synchronized';
+export {Synchronized} from './synchronized';
 export {Synchronizer} from './synchronizer';

packages/state/synchronized.js

@@ -9,7 +9,7 @@ const decorate = compose(
   Property('state'),
 );
 
-export function SynchronizedMixin(Superclass) {
+export function Synchronized(Superclass) {
   return class Synchronized extends decorate(Superclass) {
 
     constructor(...args) {
@@ -48,7 +48,10 @@ export function SynchronizedMixin(Superclass) {
       if (!(key in this)) {
         return;
       }
-      if (this[key] instanceof Synchronized) {
+      if (
+        'undefined' !== typeof this[key]
+        && 'undefined' !== typeof this[key].patchState
+      ) {
         this[key].patchState([step]);
       }
       else {
@@ -59,13 +62,19 @@ export function SynchronizedMixin(Superclass) {
     tick(elapsed) {
       const children = this.synchronizedChildren();
       for (const key of children) {
-        if (this[key] instanceof Synchronized) {
+        if (
+          'undefined' !== typeof this[key]
+          && 'undefined' !== typeof this[key].tick
+        ) {
           this[key].tick(elapsed);
         }
       }
       this.state = this.state.withMutations((state) => {
         for (const key of children) {
-          if (this[key] instanceof Synchronized) {
+          if (
+            'undefined' !== typeof this[key]
+            && 'undefined' !== typeof this[key].state
+          ) {
             state.set(key, this[key].state);
           }
           else {
@@ -77,5 +86,3 @@ export function SynchronizedMixin(Superclass) {
 
   }
 }
-
-export class Synchronized extends SynchronizedMixin(class {}) {}

packages/topdown/layer.js

@@ -21,9 +21,10 @@ const decorate = compose(
   Property('world', {
     track: true,
   }),
+  Synchronized,
 );
 
-export class Layer extends decorate(Synchronized) {
+export class Layer extends decorate(class {}) {
 
   constructor() {
     super();

packages/topdown/layers.js

@@ -8,9 +8,10 @@ import {Layer} from './layer';
 
 const decorate = compose(
   EventEmitter,
+  Synchronized,
 );
 
-export class Layers extends decorate(Synchronized) {
+export class Layers extends decorate(class {}) {
 
   constructor() {
     super();

packages/topdown/room.js

@@ -16,10 +16,11 @@ const decorate = compose(
   Vector.Mixin('size', 'width', 'height', {
     default: [0, 0],
     track: true,
-  })
+  }),
+  Synchronized,
 );
 
-export class Room extends decorate(Synchronized) {
+export class Room extends decorate(class {}) {
 
   constructor() {
     super();

packages/topdown/tiles.js

@@ -10,9 +10,10 @@ const decorate = compose(
   Vector.Mixin('size', 'width', 'height', {
     default: [0, 0],
   }),
+  Synchronized,
 );
 
-export class Tiles extends decorate(Synchronized) {
+export class Tiles extends decorate(class {}) {
 
   constructor() {
     super();