prettier-plugin-classnames

A Prettier plugin that wraps verbose class name based on the printWidth option.

Installation

For Prettier v2:

npm install -D prettier@^2 prettier-plugin-classnames

For Prettier v3:¹

npm install -D prettier prettier-plugin-classnames

Configuration

JSON example:

{
  "plugins": ["prettier-plugin-classnames"]
}

JS example (CommonJS module):

module.exports = {
  plugins: ['prettier-plugin-classnames'],
  customAttributes: ['myClassProp'],
  customFunctions: ['clsx'],
};

JS example (ES module):

export default {
  plugins: ['prettier-plugin-classnames'],
  endingPosition: 'absolute',
};

Options

Custom Attributes

List of attributes that enclosing class names.
The class and className attributes are always supported, even if no options are specified.

Default	CLI Override	API Override
[]	--custom-attributes <string>	customAttributes: ["<string>"]

Custom Functions

List of functions that enclosing class names.
The classNames function is always supported, even if no options are specified.

Default	CLI Override	API Override
[]	--custom-functions <string>	customFunctions: ["<string>"]

Ending Position

First available in v0.5.0.

This is the criterion for ending the class name on each line when replacing the original class name with a multi-line class name.

• relative example:

  --------------------------------------------------| printWidth=50
  export function Callout({ children }) {
    return (
      <div
                  |--------------------------------------------------|
        className="bg-gray-100/50 border border-zinc-400/30
         |--------------------------------------------------|
          dark:bg-neutral-900/50 dark:border-neutral-500/30
          px-4 py-4 rounded-xl"
      >
        {children}
      </div>
    );
  }
  

• absolute example:

  --------------------------------------------------| printWidth=50
  export function Callout({ children }) {
    return (
      <div
        className="bg-gray-100/50 border
  border-zinc-400/30 dark:bg-neutral-900/50
  dark:border-neutral-500/30 px-4 py-4 rounded-xl"
      >
        {children}
      </div>
    );
  }
  

• absolute-with-indent (first available in v0.6.0) example:

  --------------------------------------------------| printWidth=50
  export function Callout({ children }) {
    return (
      <div
        className="bg-gray-100/50 border
          border-zinc-400/30 dark:bg-neutral-900/50
          dark:border-neutral-500/30 px-4 py-4
          rounded-xl"
      >
        {children}
      </div>
    );
  }
  

Default	CLI Override	API Override
"relative"	--ending-position <relative|absolute|absolute-with-indent>	endingPosition: "<relative|absolute|absolute-with-indent>"

Experimental Optimization

First available in v0.7.2.

Formatting will be up to 67% faster. Note that Node.js version must be 17 or higher, and the output of nested expressions may be slightly different.

Default	CLI Override	API Override
false	--experimental-optimization	experimentalOptimization: <boolean>

Version correlation with sibling plugins

Starting with 0.6.0, when there is a minor release on one side, I plan to reflect that change on the other side as well if possible.

Compatibility with other Prettier plugins

If more than one Prettier plugin can handle the text you want to format, Prettier will only use the last of those plugins.

In this case, you can configure it as follows by adding prettier-plugin-merge to apply those plugins sequentially.

JSON example:

{
  "plugins": [
    "prettier-plugin-tailwindcss",
    "prettier-plugin-classnames",
    "prettier-plugin-merge"
  ]
}

Footnotes

1. If your version of prettier-plugin-classnames is less than 0.4.0, you will also need to install @prettier/sync. ↩