ATOMIC-TESTS.MD

Automated Atomic Tests

No, not the best tests that we can code

An automated atomic test (AAT) is one that tests only a single feature or component. An AAT should form a single irreducible unit. An automated test should not do something like end-to-end automation.

We can usually tell that a test is atomic when:

• The test will only have one assertion or two assertions at most. Because sometimes we need one assertion to make sure our state is correct
• Atomic tests have very few UI interactions and they’re only on a maximum of two screens. In rare cases, an atomic test might navigate through 3 screens (although I’d like to see this example)

Advantages of atomic tests

1. Atomic tests fail fast
2. Atomic tests decrease flaky behavior
3. Atomic checks allow for focused testing
4. Atomic tests are short and fast

As an aside, this concept is already well understood in unit and integration tests, but UI tests continue to lag behind.

Read more

The steps to creating atomic tests

1. Find the functionality that you want to test
2. Isolate/Mock/Fake all irrelevant actions
3. Test the relevant feature through UI

👀How does our app work under the hood?

Let's take a look at how a login and cart functionality works at the code level

Let's make our tests atomic

1. 🏋️‍♀️Go to E2ETests.java and follow instructions in userCanCheckoutAtomic() to create an atomic test that validates checkout logic
2. Don't forget to run the test until it passes

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❓Questions or concerns about this process

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🧪Let's review test coverage

⏭️Next, we will use visual tests to:

• Massively increase browser coverage
• Drastically decrease the code we need to maintain
• Drastically increase test suite stability

Visual testing