Book Image

Test-Driven Development in Go

By : Adelina Simion
Book Image

Test-Driven Development in Go

By: Adelina Simion

Overview of this book

Experienced developers understand the importance of designing a comprehensive testing strategy to ensure efficient shipping and maintaining services in production. This book shows you how to utilize test-driven development (TDD), a widely adopted industry practice, for testing your Go apps at different levels. You’ll also explore challenges faced in testing concurrent code, and learn how to leverage generics and write fuzz tests. The book begins by teaching you how to use TDD to tackle various problems, from simple mathematical functions to web apps. You’ll then learn how to structure and run your unit tests using Go’s standard testing library, and explore two popular testing frameworks, Testify and Ginkgo. You’ll also implement test suites using table-driven testing, a popular Go technique. As you advance, you’ll write and run behavior-driven development (BDD) tests using Ginkgo and Godog. Finally, you’ll explore the tricky aspects of implementing and testing TDD in production, such as refactoring your code and testing microservices architecture with contract testing implemented with Pact. All these techniques will be demonstrated using an example REST API, as well as smaller bespoke code examples. By the end of this book, you’ll have learned how to design and implement a comprehensive testing strategy for your Go applications and microservices architecture.
Table of Contents (18 chapters)
1
Part 1: The Big Picture
6
Part 2: Integration and End-to-End Testing with TDD
11
Part 3: Advanced Testing Techniques

Working with assertion frameworks

While the testify/mock functionality is useful for creating mocks, testify is best known for its assertion framework. In this section, we will explore some common assertion frameworks and how we can use them to further streamline and expand our tests.

So far, we have been writing our verifications using if statements and invoking the correct failure method on the testing.T parameter:

// Assert
if err != nil {
  t.Fatal(err)
}

This approach is simple, but it does have the following disadvantages:

  • Repetition: A lengthy or complex test will end up making multiple assertions. We will then have to repeat this error assertion block multiple times, making the test verbose.
  • Difficult to make advanced assertions: We want to have the same fine-grained control over the verifications we undertake on our mocks throughout the rest of the test.
  • Completely different approach to other languages: This approach is completely different...