Using Custom Decorators in Storybook.js

1. Introduction

Decorators in Storybook.js are powerful tools that allow you to modify or enhance your components' rendering environment. They enable you to wrap your stories with additional functionality, such as providing context, theming, or any other enhancements necessary for testing.

2. What are Decorators?

Decorators are functions that take a story and return a modified story, adding new props or wrapping it with a component. They are useful for:

• Providing context for components.
• Adding global styles or themes.
• Wrapping components with providers (like Redux or Context API).

3. Creating Custom Decorators

To create a custom decorator, define a function that takes a story function and returns a new function. Here’s an example of a simple custom decorator that adds a background color:

const withBackgroundColor = (color) => (Story) => {
    return (
        

            
        
    );
};
        

4. Applying Decorators

To apply your custom decorator, use the `addDecorator` function in your Storybook configuration file (usually `preview.js` or `preview.ts`). Here’s how you can apply the `withBackgroundColor` decorator:

import { addDecorator } from '@storybook/react';

addDecorator(withBackgroundColor('lightblue'));
        

5. Best Practices

When working with custom decorators, keep these best practices in mind:

• Keep decorators reusable and composable.
• Document the purpose of each decorator.
• Limit the number of decorators applied to a single story to maintain clarity.
• Test decorators separately to ensure they behave as expected.

6. FAQ