goldbergyoni

class TransferService {
async transfer({ id, sender, receiver, transferAmount, bankName }) {
    // Validation
    if (!sender || !receiver || !transferAmount || !bankName) {
      throw new Error("Some mandatory property was not provided");
    }
  
    // Handle insufficient credit
    if (this.options.creditPolicy === "zero" && sender.credit < transferAmount) {
      this.numberOfDeclined++; //incrementing interal metric

goldbergyoni

test("When no credit, the declined transfer does not appear in sender history", () => {
      // Arrange
      const transferRequest = testHelpers.factorMoneyTransfer({
        sender: { credit: 50 },
        transferAmount: 100,
      });
      const transferServiceUnderTest = new TransferService({ creditPolicy: "NoCredit" });

      // Act
      transferServiceUnderTest.transfer(transferRequest);

goldbergyoni

```
+--------------------+------------------+--------------+-------------+
|      Criteria      | Clean beforeEach | Transactions | No cleanup  |
+--------------------+------------------+--------------+-------------+
| Speed 🏎           | 6 seconds        | 7 seconds    | 5.5 seconds |
| Troubleshooting 🔍 | One test only    | No           | All tests   |
| Chaos 🐒           | No               | No           | Yes         |
| Multi-process 🚌🚌 | Harder           | Easy         | Easy        |
+--------------------+------------------+--------------+-------------+
```

goldbergyoni

beforeEach(() => {
db.Orders.destroy({truncate: false, force:true})
});

goldbergyoni

test("When deleting an existing order, Then the DB should have 0 records", async () => {
      // Arrange
      const orderToAdd = {
        userId: 1,
        productId: 2,
        invoiceId: `123`, //unique field
      };
      await request(expressApp).post("/order").send(orderToAdd);

      // Act

goldbergyoni

// ❌
  test('Should fail', () => {
    const transferRequest = testHelpers.factorMoneyTransfer({}); // ❌
    serviceUnderTest.options.creditPolicy = 'zero'; // ❌
    transferRequest.howMuch = 110; // ❌
    // Let's use the library sinon to listen to calls to the DB save function
    const databaseRepositoryMock = sinon.stub(dbRepository, 'save');//❌
    const transferResponse = serviceUnderTest.transfer(transferRequest);
    expect(transferResponse.currency).toBe('dollar'); // ❌
    expect(transferResponse.id).not.toBeNull(); // ❌

goldbergyoni

afterAll(() => {
  if (isCI) {
    dockerCompose.down();
  }
})

goldbergyoni

test('When an order error occurs, an email is sent to the admin', () => {
      //Arrange
            sinon.stub(dataAccessCode , 'saveOrder').throws(new Error('DB save failed'));
            const spyOnMailer = sinon.spy(mailer , "sendEmail");
            const orderToAdd = {userId: 1, productId: 2, mode: 'approved'}; 
          
            //Act
            const receivedResponse = await request(expressApp).post("/order").send(orderToAdd);
          
            //Assert

goldbergyoni

test("When adding a new valid order , Then should get back 200 response", async () => {
      //Arrange
      const orderToAdd = {userId: 1, productId: 2, mode: 'approved'};
      nock("http://localhost/user/")
        .get(`/1`).reply(200, {
          id: 1, name: "John"
        });

      //Act
      const receivedAPIResponse = await superTest(expressApp).post("/order").send(orderToAdd);

goldbergyoni

//Open 'mocking' sandbox
sinonSandbox = sinon.sandbox.create();