Mastering React Test-Driven Development

Writing great tests

The first test now looks like this:

it('renders the customer first name', () => {  customer = { firstName: 'Ashley' };  render(<Appointment customer={customer} />);  expect(container.textContent).toMatch('Ashley');});

This is concise and clearly readable.

A good test has three distinct sections:

• Arrange: Sets up test dependencies
• Act: Executes production code under test
• Assert: Checks expectations are met

A great test is not just good but is also the following:

• Short
• Descriptive
• Independent of other tests
• Has no side-effects