refactor(entity): JSON

packages/entity/src/resources/entity.js

@@ -371,16 +371,35 @@ export default (flecks) => {
     }
 
     toJSON() {
-      const json = {};
-      const traits = Object.entries(this.#traits);
-      for (let i = 0; i < traits.length; i++) {
-        const [type, trait] = traits[i];
-        json[type] = trait.toJSON();
+      let output;
+      if (this.uri) {
+        const pristine = {};
+        const json = {};
+        const traits = Object.entries(this.#traits);
+        for (let i = 0; i < traits.length; i++) {
+          const [type, trait] = traits[i];
+          pristine.traits = pristine.traits || {};
+          pristine.traits[type] = trait.constructor.withDefaults(
+            this.#originalJson ? this.#originalJson.traits[type] : {},
+          );
+          json.traits = json.traits || {};
+          json.traits[type] = trait.toJSON();
+        }
+        output = {
+          extends: this.uri,
+          ...(mergeDiff(pristine, json) || {}),
+        };
       }
-      return {
-        ...(this.uri ? {extends: this.uri} : {}),
-        traits: json,
-      };
+      else {
+        output = {};
+        const traits = Object.entries(this.#traits);
+        for (let i = 0; i < traits.length; i++) {
+          const [type, trait] = traits[i];
+          output.traits = {};
+          output.traits[type] = trait.toJSON();
+        }
+      }
+      return output;
     }
 
     toNetwork(informed) {

packages/entity/test/json.js

@@ -25,9 +25,9 @@ afterEach(() => {
 
 it('outputs JSON', () => {
   const entity = new Entity();
-  expect(entity.toJSON()).to.deep.equal({traits: {}});
+  expect(entity.toJSON()).to.deep.equal({});
   entity.uri = '/foo/bar';
-  expect(entity.toJSON()).to.deep.equal({extends: entity.uri, traits: {}});
+  expect(entity.toJSON()).to.deep.equal({extends: entity.uri});
 });
 
 it('can trim defaults from JSON', async () => {