How can I automate tests in a MERN application?

How can I automate tests in a MERN application?

You can automate tests in a MERN application using tools like Jest for unit testing and Cypress for end-to-end testing.

What is Jest and how do I set it up?

Jest is a JavaScript testing framework. You can set it up by installing it via npm with npm install --save-dev jest and configuring it in your package.json.

Can you give me an example of a test case?

Sure! Here's a simple test case for a function:

function add(a, b) {
  return a + b;
}

test('adds 1 + 2 to equal 3', () => {
  expect(add(1, 2)).toBe(3);
});

How do I run the tests once they're written?

You can run your tests by executing the command npm test in your terminal, which will trigger Jest to run all test files.