test: add unit tests for DAOs

src/app/dao/PurchaseDAO.spec.ts

@@ -0,0 +1,95 @@
+import { TestBed } from '@angular/core/testing';
+import { PurchaseDAO } from './PurchaseDAO';
+import { Sqlite } from '../services/sqlite';
+import { Purchase } from '../models/Purchase';
+import { Establishment } from '../models/Establishment';
+import { Chain } from '../models/Chain';
+import { Product } from '../models/Product';
+import { PurchaseQueryResult } from '../types/sqlite.type';
+
+describe('PurchaseDAO', () => {
+  let service: PurchaseDAO;
+  let sqlite: Partial<Sqlite>;
+
+  let PURCHASE_MOCK: Purchase;
+  let PURCHASE_QUERY_RESULT_MOCK: PurchaseQueryResult;
+
+  beforeEach(() => {
+    PURCHASE_MOCK = new Purchase(
+      new Establishment(new Chain('mock', 'mock.jpg', 1), 'mock street', 1),
+      new Product('1212112', 'mock', 'mock.png', 1),
+      1245.55,
+      3,
+      Date.now(),
+      1,
+    );
+    PURCHASE_QUERY_RESULT_MOCK = {
+      address: PURCHASE_MOCK.establishment.address,
+      barcode: PURCHASE_MOCK.product.barcode,
+      chain_id: PURCHASE_MOCK.establishment.chain.id!,
+      chain_image: PURCHASE_MOCK.establishment.chain.image,
+      chain_name: PURCHASE_MOCK.establishment.chain.name,
+      date: PURCHASE_MOCK.date,
+      establishment_id: PURCHASE_MOCK.establishment.id!,
+      id: PURCHASE_MOCK.id!,
+      price: PURCHASE_MOCK.price,
+      product_id: PURCHASE_MOCK.product.id!,
+      product_image: PURCHASE_MOCK.product.image,
+      product_name: PURCHASE_MOCK.product.name,
+      quantity: PURCHASE_MOCK.quantity,
+    };
+
+    sqlite = {
+      executeQuery: vi.fn().mockResolvedValue({ rows: [PURCHASE_QUERY_RESULT_MOCK] }),
+    };
+
+    TestBed.configureTestingModule({
+      providers: [{ provide: Sqlite, useValue: sqlite }],
+    });
+
+    service = TestBed.inject(PurchaseDAO);
+  });
+
+  it('should be created', () => {
+    expect(PURCHASE_MOCK).toBeTruthy();
+  });
+
+  it('should receive mapped results on findAll', async () => {
+    const result = await service.findAll();
+    if (result.length > 0) {
+      expect(result[0]).toEqual(PURCHASE_MOCK);
+    } else {
+      test.fails('Expected mock response to contain at least one value');
+    }
+  });
+
+  it('should call executeQuery with object fields on insert', async () => {
+    sqlite.executeQuery = vi.fn().mockResolvedValue({ rows: [] });
+    const expectedSql =
+      'INSERT INTO purchase ( establishment_id, product_id, date, price, quantity ) VALUES ( ?, ?, ?, ?, ? );';
+    const expectedParams: any[] = [
+      PURCHASE_MOCK.establishment.id,
+      PURCHASE_MOCK.product.id,
+      PURCHASE_MOCK.date,
+      PURCHASE_MOCK.price * 100,
+      PURCHASE_MOCK.quantity,
+    ];
+    PURCHASE_MOCK.id = undefined;
+    await service.insert(PURCHASE_MOCK);
+    expect(sqlite.executeQuery).toHaveBeenCalledExactlyOnceWith(expectedSql, expectedParams);
+  });
+
+  describe('toDB', () => {
+    it('should throw if toDB is called with a establishmen that has no id', async () => {
+      sqlite.executeQuery = vi.fn().mockResolvedValue({ rows: [] });
+      PURCHASE_MOCK.establishment.id = undefined;
+      expect(service.insert(PURCHASE_MOCK)).rejects.toThrow();
+    });
+
+    it('should throw if toDB is called with a product that has no id', async () => {
+      sqlite.executeQuery = vi.fn().mockResolvedValue({ rows: [] });
+      PURCHASE_MOCK.product.id = undefined;
+      expect(service.insert(PURCHASE_MOCK)).rejects.toThrow();
+    });
+  });
+});