Gain expertise in testing Elixir applications with ExUnit, unit testing principles, and integration with OTP, Phoenix, JSON APIs, and Ecto.

Test Your Web Applications with Elixir

Testing is an essential part of the software development life cycle. A good automated testing suite streamlines feedback, allowing rapid creation and tight control over specific application components.

This module is a comprehensive introduction to testing Elixir applications with ExUnit. We'll start with a review of unit testing principles before diving into writing tests with ExUnit. We’ll build a comprehensive suite of unit tests before moving on to more advanced testing, including integration, end-to-end, and property-based testing. In addition to the core Elixir environment, we’ll develop tests for OTP, the Phoenix web framework, JSON APIs, and Ecto schematics. We’ll also explore refactoring, server rendering, and design strategies for different platforms.

By the end of this module, we’ll have gained expertise in unit testing Elixir applications with ExUnit and be ready to build robust, performant applications using Phoenix.

Ensuring Elixir Application Performance with Testing and ExUnit

test the functionality of different modules within an application

test the correctness of a function within an application

test the coordination of different functions with each other

test the functionality of the system as a whole

**(Fill in the blank.)** Integration tests are performed to ________.

(Fill in the blank.) Integration tests are performed to ________.

**(True or False)** A controller function is responsible for rerouting request data.

(True or False) A controller function is responsible for rerouting request data.

**(True or False)** If we can adequately do unit testing, there is no need to do integration testing and vice versa.

(True or False) If we can adequately do unit testing, there is no need to do integration testing and vice versa.

**(True or False)**  Integration tests can be performed between components of our system as well as external systems.

(True or False) Integration tests can be performed between components of our system as well as external systems.

You may clutter the database with redundant entries.

The local database is faster than its dependency double.

One approach for dealing with the external dependency is to use the real dependency.

An external service is a dependency that we have complete control over. 

**(Select all that apply.)**  If a local database is considered as an external dependency to perform an integration test, which statements are true?

(Select all that apply.) If a local database is considered as an external dependency to perform an integration test, which statements are true?

Behaviors clearly define the boundaries of the test unit

**(Fill in the blank.)** One of the main benefits of using Behaviors is that ________.

(Fill in the blank.) One of the main benefits of using Behaviors is that ________.

**(Select all that apply.)** Which doubles are the most useful when combined?

(Select all that apply.) Which doubles are the most useful when combined?

**(True or False)** Mox is added as a dependency in the test environment only.

(True or False) Mox is added as a dependency in the test environment only.

Take a short quiz to test your understanding of the concepts of integration testing.

Unit Tests

Integration and End-to-End Tests

Testing OTP

Testing Ecto Schemas

Testing Ecto Queries

Testing Phoenix

Property-Based Testing

Conclusion

Quiz on Integration Testing I