Скачать или смотреть Solving TypeError in Vitest with Styled Components

Discover how to configure Vitest and Styled Components effectively in your React project to resolve common errors, including a detailed solution using Enzyme.
---
This video is based on the question https://stackoverflow.com/q/76588750/ asked by the user 'Ali Mardini' ( https://stackoverflow.com/u/7445566/ ) and on the answer https://stackoverflow.com/a/76603472/ provided by the user 'Ali Mardini' ( https://stackoverflow.com/u/7445566/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: How to configure Vitest and Styled Components?

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Solving TypeError in Vitest with Styled Components: A Step-by-Step Guide

Working with React projects that utilize styled-components can sometimes lead to frustrating issues, especially when testing with Vitest. A common error encountered is the TypeError: Cannot read properties of undefined (reading 'borderRadius'). This guide aims to explore this problem and provide a comprehensive guide on how to configure Vitest to work seamlessly with Styled Components.

Understanding the Problem

You might have come across the error while running your tests in a React project created with Vite and using TypeScript. The error typically points to a line in your styles file that attempts to access a property of the theme that hasn't been defined, especially when certain component properties aren't passed correctly during testing.

Here's a sample of what the error might look like:

[[See Video to Reveal this Text or Code Snippet]]

You may be familiar with similar situations in Jest, where you could easily handle these cases using the jest-styled-components package. However, with Vitest, the same approach doesn’t apply directly, leaving you in need of an alternative solution.

Proposed Solution: Using Enzyme's Shallow Rendering

After some extensive research and testing, one effective solution is to use shallow rendering from Enzyme. This method helps create a shallow copy of your components, allowing you to bypass issues related to deep rendering and theme properties.

Step 1: Installing Enzyme

First, make sure you have Enzyme installed in your React project. Run the following command in your terminal:

[[See Video to Reveal this Text or Code Snippet]]

Make sure to modify the adapter version according to your React version.

Step 2: Setting Up Your Test File

Now, let’s update your test file to utilize Enzyme’s shallow rendering feature. Below is an example of how to configure your tests:

[[See Video to Reveal this Text or Code Snippet]]

A Quick Breakdown of the Code

Imports: The shallow function from Enzyme allows us to create a shallow copy of the Button component.

wrapper Variable: This holds the instance of the shallow-rendered component.

Tests: We define multiple tests checking if the component renders correctly, whether the button click triggers the onClick prop, and if the rendered output matches the snapshot.

Advantages of Using Shallow Rendering

Isolation: Tests focus on the component's behavior instead of its children's behavior.

Speed: Shallow rendering is faster than mounting because it does not dive into child components.

Simplicity: Helps in tracking down errors related to props or theme properties more effectively.

Conclusion

Configuring Vitest to work with Styled Components can be a hassle at times, but employing shallow rendering with Enzyme can significantly alleviate the issues you may encounter with property reading errors. This method not only simplifies your testing process but also enhances your component isolation.

By following the steps provided, you should have a smoother experience while testing your React components within a Vitest environment. Happy coding!