feat: traits HMR!

packages/entity/src/hot-entities.js

@@ -0,0 +1 @@
+export default new Set();

packages/entity/src/index.js

@@ -1,5 +1,6 @@
 import {gatherWithLatus} from '@latus/core';
 
+import hotEntities from './hot-entities';
 import types from './types';
 
 export {default as EntityListView} from './entity-list-view';
@@ -10,6 +11,20 @@ export default {
     '@avocado/resource/resources': gatherWithLatus(
       require.context('./resources', false, /\.js$/),
     ),
+    '@avocado/traits/hmr': (Trait, type) => {
+      const it = hotEntities.values();
+      for (let current = it.next(); current.done !== true; current = it.next()) {
+        const {value: entity} = current;
+        if (entity.is(type) && entity.trait(type).hotJSON) {
+          const json = {
+            ...entity.trait(type).toJSON(),
+            ...entity.trait(type).hotJSON(),
+          };
+          entity.removeTrait(type);
+          entity.addTrait(type, json);
+        }
+      }
+    },
     '@avocado/traits/traits': gatherWithLatus(
       require.context('./traits', false, /\.js$/),
     ),

packages/entity/src/resources/entity.js

@@ -11,6 +11,7 @@ import {compose, EventEmitter} from '@latus/core';
 
 import {defineTraitAccessors, enumerateTraitAccessorKeys} from '../accessors';
 import BaseEntity from '../base-entity';
+import hotEntities from '../hot-entities';
 
 const debug = D('@avocado/entity');
 
@@ -58,6 +59,9 @@ export default (latus) => {
       this.room = null;
       this.uptime = 0;
       this.visibleAabb = [0, 0, 0, 0];
+      if (module.hot) {
+        hotEntities.add(this);
+      }
     }
 
     addTickingPromise(tickingPromise) {
@@ -189,6 +193,9 @@ export default (latus) => {
         return;
       }
       this.#isDestroying = true;
+      if (module.hot) {
+        hotEntities.delete(this);
+      }
       const destroyers = this.invokeHookFlat('destroy');
       if (destroyers.length > 0) {
         await this.addTickingPromise(new TickingPromise(

packages/traits/src/index.js

@@ -8,6 +8,31 @@ export default {
     '@latus/core/config': () => ({
       'traits.decorate': ['...'],
     }),
+    '@latus/core/hmr': (path, latus) => {
+      const Traits = latus.invokePlugin('@avocado/traits/traits', path);
+      if (!Traits) {
+        return;
+      }
+      const entries = Object.entries(Traits);
+      for (let i = 0; i < entries.length; ++i) {
+        const [type, Trait] = entries[i];
+        const {[type]: {id}} = latus.get('%traits');
+        class Wrapped extends Trait {
+
+          static get type() {
+            return type;
+          }
+
+          static get id() {
+            return id;
+          }
+
+        }
+        latus.set(`%traits.${type}`, Wrapped);
+        latus.set(`%traits.${id}`, Wrapped);
+        latus.invoke('@avocado/traits/hmr', Wrapped, type);
+      }
+    },
     '@latus/core/starting': (latus) => {
       latus.set('%traits', gather(
         latus,