feat: throw error when accessing model.$store without store being injected (#2)

Author: kiaking

src/model/Model.ts

@@ -1,5 +1,5 @@
 import { Store } from 'vuex'
-import { isArray } from '../support/Utils'
+import { isArray, assert } from '../support/Utils'
 import { Element, Item, Collection } from '../data/Data'
 import { Attribute } from './attributes/Attribute'
 import { Attr } from './attributes/types/Attr'
@@ -194,6 +194,12 @@ export class Model {
    * Get the store instance.
    */
   get $store(): Store<any> {
+    assert(this._store !== undefined, [
+      'A Vuex Store instance is not injected into the model instance.',
+      'You might be trying to instantiate the model directly. Please use',
+      '`repository.make` method to create a new model instance.'
+    ])
+
     return this._store
   }
 

src/support/Utils.ts

@@ -198,3 +198,13 @@ export function cloneDeep<T extends object>(target: T): T {
 
   return target
 }
+
+/**
+ * Check for the given condition, and if it's `false`, it will throw a new
+ * error with the given message.
+ */
+export function assert(condition: boolean, message: string[]): void {
+  if (!condition) {
+    throw new Error(['[Vuex ORM]'].concat(message).join(' '))
+  }
+}

test/unit/model/Model.spec.ts

@@ -0,0 +1,11 @@
+import { Model } from '@/model/Model'
+
+describe('unit/model/Model', () => {
+  class User extends Model {
+    static entity = 'users'
+  }
+
+  it('throws when accessing the store but it is not injected', () => {
+    expect(() => new User().$store).toThrow()
+  })
+})