fix(webiny-entity): EntityCollection must only accept instances of En…

…tity class.

close #6, close #18

packages-api/webiny-entity/src/entityAttributes/entitiesAttribute.js

@@ -158,7 +158,7 @@ class EntitiesAttribute extends Attribute {
      * @param value
      * @returns {Promise<void>}
      */
-    setValue(value): Promise<void> {
+    setValue(value): any {
         return new Promise((resolve, reject) => {
             this.value.load(() => {
                 if (!this.canSetValue()) {
@@ -211,7 +211,7 @@ class EntitiesAttribute extends Attribute {
      * It will return only valid IDs, other values will be ignored because they must not enter storage.
      * @returns {Promise<*>}
      */
-    async getStorageValue() {
+    async getStorageValue(): any {
         if (_.isArray(this.value.getCurrent())) {
             // Not using getValue method because it would load the entity without need.
             const storageValue = [];

packages-api/webiny-entity/src/entityCollection.js

@@ -6,14 +6,17 @@ class EntityCollection extends Array<Entity> {
 
     constructor(values: Array<Entity> = []) {
         super();
-        if (!values.forEach) {
-            values = [];
-        }
-        values.forEach(v => this.push(v));
-        this.entityCollection = {
-            params: null,
-            meta: null
-        };
+        this.entityCollection = { params: null, meta: null };
+        values.forEach &&
+            values.forEach(item => {
+                if (item instanceof Entity) {
+                    this.push(item);
+                    return true;
+                }
+                throw Error(
+                    "EntityCollection cannot accept a value that is not an instance of Entity."
+                );
+            });
     }
 
     setParams(params: Object): this {

packages-api/webiny-entity/tests/entityCollection.test.js

@@ -0,0 +1,41 @@
+import { assert, expect } from "chai";
+import User from "./entities/user";
+import { EntityCollection } from "./..";
+
+const getEntities = () => [
+    new User().populate({ age: 30 }),
+    new User().populate({ age: 35 }),
+    new User().populate({ age: 40 })
+];
+
+describe("EntityCollection test", function() {
+    it("must correctly accept an array of entities", async () => {
+        const entities = getEntities();
+        const collection = new EntityCollection(entities);
+        expect(collection).to.have.lengthOf(3);
+        expect(collection[0].age).to.equal(30);
+        expect(collection[1].age).to.equal(35);
+        expect(collection[2].age).to.equal(40);
+    });
+
+    it("must correctly push new entities", async () => {
+        const entities = getEntities();
+        const collection = new EntityCollection(entities);
+
+        collection.push(new User().populate({ age: 45 }));
+        expect(collection).to.have.lengthOf(4);
+        expect(collection[3].age).to.equal(45);
+
+        expect(() => collection.push(1)).to.throw(Error);
+        expect(() => collection.push({ age: 50 })).to.throw(Error);
+
+        expect(collection).to.have.lengthOf(4);
+        expect(collection[3].age).to.equal(45);
+    });
+
+    it("must throw an error on construct, if one of the values is not an instance of Entity", async () => {
+        expect(() => {
+            new EntityCollection([new User(), new User(), { id: 123 }]);
+        }).to.throw(Error);
+    });
+});