Unit testing is a software development and testing method in which the least testable parts of an application, called units, are separately and individually tested to see if they are operating correctly. Unit testing can be performed manually but is usually automated. Unit testing is a part of the test-driven development (TDD) methodology that needs developers to first write crashing unit tests. Then, they write code in order to modify the application until the test qualifies. Writing the failing test is necessary because it requires the developer to take into account all possible inputs, errors, and outputs.
The outcome of using TDD is that an Agile team can gain a comprehensive suite of unit tests that can be run at any time to give feedback that their software is still running. If the new code breaks something and makes a test to fail, TDD also makes it simpler to pinpoint the problem, refactor the application, and fix the bug.
The AAA Pattern
The purpose of unit testing is to separate all parts of a program and determine that the individual parts work accurately.
Unit test automation is a fundamental element of a Continuous Delivery DevTestOps solution, that is, a continuously examined, two-way DevOps software delivery pipeline between an organization and its customers.
Unit tests are created for code that has no external dependencies, such as calls to the database or web services. Because they concentrate on a particular behavior in a small section of a system under test (SUT), they’re also comparatively straightforward to automate, especially if they are written in a usual format such as the AAA pattern.
The AAA (Arrange, Act, Assert) pattern helps build and clarify test code by dividing down a test case into the following functional parts:
The Arrange section of a unit test initializes objects and fixes the value of the data that is transferred to the test case.
The Act section invokes the test case with the determined parameters.
The Assert section verifies the test case works as expected.
Consider the following example test scenario:
A unit test in AAA format tests a software unit that increments the number of products in an e-commerce shopping cart:
Arrange: Create an empty shopping cart.
Act: Append a product to the cart.
Assert: Number of products in cart raised by one.
The Understanding of World With a Comprehensive Automated Testing Strategy
Will introducing unit tests and test automation save you from encountering difficulties, defects, or tests? No, of course not. It’s not a cure.
But it will give you an important advantage, saving you time, money, and stress. Think of the relative benefits of, say, signing a bunch of employee paychecks by hand versus having payroll software that makes direct deposits.
The issues won’t go away completely, but your life will go from an infinite high-stress grind to one where you can concentrate on things other than hand-writing checks and trying not to make errors out of boredom. End-to-end testing is really about that.
Connect with TestUnity and let our experienced team take care of testing while you can focus on your business outcomes, building stuff, and hitting your deadlines