Unit Testing with Brain Monkey

How can you unit test your plugin or theme without WordPress or other dependencies? You simulate the dependencies. My favorite tool to redefine and mock functions is Brain Monkey. In this hands-on testing lab, you will actively write unit tests using Brain Monkey.

The challenge we have when unit testing a plugin or theme is how to force the expected behavior of dependent functions. For objects, we can use Mockery. But for functions, we need another tool.

Huh? For example, your plugin or theme will likely have various WordPress functions, such as add_action, add_filter, wp_normalize_path, esc_html, esc_attr, and many others. Right? We use these functions all the time. But how can you unit test your code without loading WordPress?

My favorite tool is Brain Monkey by Giuseppe Mazzapica. Seriously, it’s an amazing testing utility for redefining and mocking dependent functions.

In this lab, you will dive deep into Brain Monkey to discover how to build unit tests without loading WordPress or any other dependency.

Unit Testing in a Nutshell

A pure unit test validates a single scenario for a single function without its dependencies, i.e. the function all by itself in isolation.

Our code has a single expected behavior for each set of conditions. We call this a scenario. We use testing techniques to validate each of these scenarios.

An integration test validates our code with all of the dependencies, including WordPress. But a unit test seeks to test only your code and not the functions you use within your code.

For example, let’s say your plugin or theme has a function that uses get_the_ID(). You unit test your code and not get_the_ID(), as get_the_ID() has its own tests. In your tests, you force get_the_ID() to give you either a post ID, such as 47, or false.

Brain Monkey gives us the toolset we need to achieve these results.

What You Will Learn

In this lab, you will be actively building unit tests as you learn deeply about the process and Brain Monkey. As a test subject, you will write unit tests for beans_get_post_meta() function in the Beans framework.

You’ll learn:

The process of dynamically redefining a function.
What Brain Monkey is and each of its toolsets.
Deciding when to use when vs. expect.
How to force a behavior or returned value from a mocked function.
How to actively test the number of times a function is called.
How to actively test the arguments being passed to the function.
and much more.

This lab has several code challenges too.

Prerequisites

21 Episodes
04:26:49 Runtime

Unit & Integration Testing Basics

Testing is a critical component of your workflow, as it validates each piece of your code to ensure it works exactly as you intended. As a professional developer, testing is a skill that will set you a part and give you a competitive advantage in the marketplace. In this hands-on lab, you will be building unit and integration tests as you learn the basics of PHP testing.

Learn more

There’s a time to code and …. yup, that sums it up.

Episodes

Total Lab Runtime: 03:21:08

0 Lab Setupfree 07:07
1 The Problem - Why We Need to Simulatefree 24:50
2 Behind the Scenes of Redefining a Functionfree 20:31
3 Brain Monkey's Toolset Overviewpro 09:04
4 Anatomy of the Test Expectationpro 11:51
5 setUp and tearDownpro 09:51
6 Create a Test Classpro 20:42
7 `when()`pro 14:23
8 `when()` - Behavior Optionspro 14:26
9 `when()` - Code Challengepro 08:27
10 `expect()`pro 11:40
11 `with()`pro 05:44
12 More with `with()`pro 10:02
13 `with()` - Code Challengepro 09:53
14 `expect()` - Behavior Optionspro 07:47
15 `andAlsoExpectIt()`pro 10:46
16 `stubs()`pro 04:04

Coming Soon

Testing Hooks with Brain Monkey

Our themes and plugins use hooks to run code when an event fires. We use WordPress' functions to add or remove a hooked callback, fire the event, or check the status. How do you unit test those interactions without loading WordPress? Meet Brain Monkey. Brain Monkey gives you the power to unit test hooks by simulating WordPress. In this lab, you'll walk through building unit tests for hooks.

Learn more

Check out the PHP Library for more hands-on labs, insights, Docx, and more.

Check out the series page for more labs: Master Tester Series

Unit Testing with Brain Monkey

What You Will Learn

Prerequisites

Unit & Integration Testing Basics

Episodes

What to Do Next?

Testing Hooks with Brain Monkey

Learn

Help

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