# css-selector-extract

> Extract certain CSS selectors form CSS code

Latest version **4.0.1** (published 2023-08-21) · MIT license · 0 weekly downloads

## Install

```sh
npm install css-selector-extract
pnpm add css-selector-extract
yarn add css-selector-extract
bun add css-selector-extract
```

## Health

**Score 20/100 (F)** — status: abandoned.

Positive: esm support; no vulnerabilities.

Warnings: low downloads; no types.

Negative: abandoned; low maintenance score.

## Facts

| | |
|---|---|
| Version | 4.0.1 |
| Published | 2023-08-21 |
| First published | 2016-06-16 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | none |
| Module format | ESM + CommonJS |
| Dependencies | 1 |
| Unpacked size | 33.6 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 13 |
| Author | Markus Oberlehner |
| Maintainers | maoberlehner |
| Keywords | CSS |

## Links

- npm: https://www.npmjs.com/package/css-selector-extract
- Repository: https://github.com/maoberlehner/css-selector-extract
- Issues: https://github.com/maoberlehner/css-selector-extract/issues
- npm.io page: https://npm.io/package/css-selector-extract

## Dependencies (1)

- [postcss](https://npm.io/package/postcss.md) ^8.2.13

## Alternatives

- [style-dictionary](https://npm.io/package/style-dictionary.md) — 2.0M weekly downloads
- [postcss-merge-idents](https://npm.io/package/postcss-merge-idents.md) — 1.7M weekly downloads
- [@fontsource/noto-sans](https://npm.io/package/@fontsource/noto-sans.md) — 93.0K weekly downloads
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- [mat4-interpolate](https://npm.io/package/mat4-interpolate.md) — 23.3K weekly downloads

## Recent versions

- 4.0.1 (latest) — 2023-08-21
- 4.0.0 — 2018-04-18
- 3.3.6 — 2017-12-12
- 3.3.5 — 2017-11-22
- 3.3.4 — 2017-11-04
- 3.3.3 — 2017-10-31
- 3.3.2 — 2017-10-31
- 3.3.1 — 2017-09-17
- 3.3.0 — 2017-09-17
- 3.2.0 — 2017-09-16
- 3.1.3 — 2017-08-11
- 3.1.2 — 2017-08-11
- 3.1.1 — 2017-08-10
- 3.1.0 — 2017-08-10
- 3.0.1 — 2017-05-31
- … 26 more at https://npm.io/package/css-selector-extract/versions

## README

# css-selector-extract

[![Patreon](https://img.shields.io/badge/patreon-donate-blue.svg)](https://www.patreon.com/maoberlehner)
[![Donate](https://img.shields.io/badge/Donate-PayPal-blue.svg)](https://paypal.me/maoberlehner)
[![Build Status](https://travis-ci.org/maoberlehner/css-selector-extract.svg?branch=master)](https://travis-ci.org/maoberlehner/css-selector-extract)
[![Coverage Status](https://coveralls.io/repos/github/maoberlehner/css-selector-extract/badge.svg?branch=master)](https://coveralls.io/github/maoberlehner/css-selector-extract?branch=master)
[![GitHub stars](https://img.shields.io/github/stars/maoberlehner/css-selector-extract.svg?style=social&label=Star)](https://github.com/maoberlehner/css-selector-extract)

With selector extracting, it is possible to extract certain CSS selectors (RegEx can be used to match selectors) from CSS code. This is especially useful if you want to extract only a few CSS classes from a huge library or framework.

## Demos

```js
const cssSelectorExtract = require('css-selector-extract');

const options = {
  // CSS source code as string.
  css: '.btn { } .btn-alert { } .btn-success { }',
  // Array of selectors which should get extracted.
  filters: ['.btn']
};

// Asynchronous:
cssSelectorExtract.process(options).then((extractedCss) => {
  console.log(extractedCss); // Outputs: `.btn { }`.
});

// Synchronous:
const extractedCss = cssSelectorExtract.processSync(options);
console.log(extractedCss); // Outputs: `.btn { }`.
```

### Rename extracted selectors

```js
const cssSelectorExtract = require('css-selector-extract');

const options = {
  // CSS source code as string.
  css: '.btn { } .btn-alert { } .btn-success { }',
  // Array of selector filter objects with selectors
  // which should get extracted and replaced.
  filters: [{ selector: '.btn', replacement: '.button' }]
};

// Asynchronous:
cssSelectorExtract.process(options).then((extractedCss) => {
  console.log(extractedCss); // Outputs: `.button { }`.
});
```

### RegEx

#### Filter selectors

```js
const cssSelectorExtract = require('css-selector-extract');

const options = {
  css: '.btn { } .btn-alert { }',
  filters: [/^\..+-alert/]
};

cssSelectorExtract.process(options).then((extractedCss) => {
  console.log(extractedCss); // Outputs: `.btn-alert { }`.
});
```

#### Replace selectors

```js
const cssSelectorExtract = require('css-selector-extract');

const options = {
  css: '.btn { } .btn-alert { }',
  filters: [{ selector: /^\.btn(.*)/, replacement: '.button$1' }]
};

cssSelectorExtract.process(options).then((extractedCss) => {
  console.log(extractedCss); // Outputs: `.button { } .button-alert { }`.
});
```

### Usage with syntaxes other than pure CSS

Install the corresponding postcss syntax plugin (e.g. [postcss-scss](https://www.npmjs.com/package/postcss-scss) or [postcss-less](https://www.npmjs.com/package/postcss-less)).

```js
const cssSelectorExtract = require('css-selector-extract');
const postcssScss = require('postcss-scss');

const options = {
  css: '.nested { .selector { } }',
  filters: ['.nested'],
  postcssSyntax: postcssScss
};

cssSelectorExtract.process(options).then((extractedCss) => {
  console.log(extractedCss);
});
```

### Preserve lines

Usually `css-selector-extract` removes all nodes which do not match the given selectors. However under some circumstances it might be useful to preserve the original line numbers (e.g. to keep source map references intact).

```js
const cssSelectorExtract = require('css-selector-extract');

const options = {
  css: '.multiple { } .selectors {}',
  filters: ['.some-selector'],
  preserveLines: true
};

cssSelectorExtract.process(options).then((extractedCss) => {
  // Outputs the extracted selector(s) with empty lines where
  // other selectors got removed to preserve line numbers.
  console.log(extractedCss);
});
```

### ES2015 named exports

```js
import { process, processSync } from 'css-selector-extract';

const options = {
  // CSS source code as string.
  css: '.btn { } .btn-alert { } .btn-success { }',
  // Array of selectors which should get extracted.
  filters: ['.btn']
};

// Asynchronous:
process(options).then((extractedCss) => {
  console.log(extractedCss); // Outputs: `.btn { }`.
});

// Synchronous:
const extractedCss = processSync(options);
console.log(extractedCss); // Outputs: `.btn { }`.
```

## Upgrade from 2.x.x to 3.x.x

With version 3.0.0 css-selector-extract takes an object as it's only parameter.

```js
const cssSelectorExtract = require('css-selector-extract');
const postcssScss = require('postcss-scss');

// New way:
const options = {
  css: '.btn { } .btn-alert { } .btn-success { }',
  filters: ['.btn'],
  postcssSyntax: postcssScss
};
cssSelectorExtract.process(options);
cssSelectorExtract.processSync(options);

// Old way:
const css = '.btn { } .btn-alert { } .btn-success { }';
const selectorFilters = ['.btn'];
cssSelectorExtract.process(css, selectorFilters, postcssScss);
cssSelectorExtract.processSync(css, selectorFilters, postcssScss);
```

## Development

See [CONTRIBUTING.md](https://github.com/maoberlehner/css-selector-extract/blob/master/CONTRIBUTING.md)

### Testing

```bash
npm test
```

## About

### Author

Markus Oberlehner  
Website: https://markus.oberlehner.net  
Twitter: https://twitter.com/MaOberlehner  
PayPal.me: https://paypal.me/maoberlehner  
Patreon: https://www.patreon.com/maoberlehner

### License

MIT

---
_Source: https://npm.io/package/css-selector-extract · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._