add small test

Author: iisa

src/monthly-giving-circle.ts

@@ -14,6 +14,7 @@ import './presentational/mgc-button';
 import type { MonthlyPlan } from './models/plan';
 import './edit-plan-form';
 import type { IauxEditPlanForm } from './edit-plan-form';
+import { Receipt } from './models/receipt';
 
 export type APlanUpdate = {
   plan?: MonthlyPlan;
@@ -43,7 +44,7 @@ export class MonthlyGivingCircle extends LitElement {
 
   @property({ type: Boolean }) canEditPaymentMethod: boolean = false;
 
-  @property({ type: Array }) receipts = [];
+  @property({ type: Array }) receipts: Receipt[] = [];
 
   @property({ type: Array }) updates: APlanUpdate[] = [];
 

test/receipt-email-request-flow.test.ts

@@ -37,6 +37,8 @@ describe('Receipts: When requesting an email', () => {
         ></ia-monthly-giving-circle>`,
       );
 
+      expect(el.receipts.length).to.equal(1);
+
       // open receipt view
       const titleEl = el.querySelector('ia-mgc-title');
       const receiptsDisplayButton = titleEl!.querySelector(