Custom Builds and Testing CLI Commands

With any Golang application, you’ll need to build and test. However, it is increasingly important as the project and its user base grow. Build tags with Boolean logic give you the ability to create targeted builds and testing and further stabilize your project with each new feature.

Given a deeper understanding of build tags and how to use them, we will use a real-world example, the audio file CLI, to integrate levels (free and pro) and enable a profiling feature.

Build tags are not only used as input when building but also when testing. We will spend the latter half of this chapter on testing. We will learn specifically how to mock an HTTP client that our CLI is using, configure tests locally, write tests for individual commands, and run them. In this chapter, we will cover the following topics in detail:

• What are build tags and how can you use them?
• Building with tags
• Testing CLI commands