forked from lix-project/lix-website
151 lines
3.6 KiB
Markdown
151 lines
3.6 KiB
Markdown
|
[tests]: https://img.shields.io/circleci/project/github/shellscape/postcss-less.svg
|
||
|
[tests-url]: https://circleci.com/gh/shellscape/postcss-less
|
||
|
|
||
|
[cover]: https://codecov.io/gh/shellscape/postcss-less/branch/master/graph/badge.svg
|
||
|
[cover-url]: https://codecov.io/gh/shellscape/postcss-less
|
||
|
|
||
|
[size]: https://packagephobia.now.sh/badge?p=postcss-less
|
||
|
[size-url]: https://packagephobia.now.sh/result?p=postcss-less
|
||
|
|
||
|
[PostCSS]: https://github.com/postcss/postcss
|
||
|
[PostCSS-SCSS]: https://github.com/postcss/postcss-scss
|
||
|
[LESS]: http://lesless.org
|
||
|
[Autoprefixer]: https://github.com/postcss/autoprefixer
|
||
|
[Stylelint]: http://stylelint.io/
|
||
|
|
||
|
# postcss-less
|
||
|
|
||
|
[![tests][tests]][tests-url]
|
||
|
[![cover][cover]][cover-url]
|
||
|
[![size][size]][size-url]
|
||
|
|
||
|
A [PostCSS] Syntax for parsing [LESS]
|
||
|
|
||
|
_Note: This module requires Node v6.14.4+. `poscss-less` is not a LESS compiler. For compiling LESS, please use the official toolset for LESS._
|
||
|
|
||
|
## Install
|
||
|
|
||
|
Using npm:
|
||
|
|
||
|
```console
|
||
|
npm install postcss-less --save-dev
|
||
|
```
|
||
|
|
||
|
<a href="https://www.patreon.com/shellscape">
|
||
|
<img src="https://c5.patreon.com/external/logo/become_a_patron_button@2x.png" width="160">
|
||
|
</a>
|
||
|
|
||
|
Please consider [becoming a patron](https://www.patreon.com/shellscape) if you find this module useful.
|
||
|
|
||
|
## Usage
|
||
|
|
||
|
The most common use of `postcss-less` is for applying PostCSS transformations directly to LESS source. eg. ia theme written in LESS which uses [Autoprefixer] to add appropriate vendor prefixes.
|
||
|
|
||
|
```js
|
||
|
const syntax = require('postcss-less');
|
||
|
postcss(plugins)
|
||
|
.process(lessText, { syntax: syntax })
|
||
|
.then(function (result) {
|
||
|
result.content // LESS with transformations
|
||
|
});
|
||
|
```
|
||
|
|
||
|
## LESS Specific Parsing
|
||
|
|
||
|
### `@import`
|
||
|
|
||
|
Parsing of LESS-specific `@import` statements and options are supported.
|
||
|
|
||
|
```less
|
||
|
@import (option) 'file.less';
|
||
|
```
|
||
|
|
||
|
The AST will contain an `AtRule` node with:
|
||
|
|
||
|
- an `import: true` property
|
||
|
- a `filename: <String>` property containing the imported filename
|
||
|
- an `options: <String>` property containing any [import options](http://lesscss.org/features/#import-atrules-feature-import-options) specified
|
||
|
|
||
|
### Inline Comments
|
||
|
|
||
|
Parsing of single-line comments in CSS is supported.
|
||
|
|
||
|
```less
|
||
|
:root {
|
||
|
// Main theme color
|
||
|
--color: red;
|
||
|
}
|
||
|
```
|
||
|
|
||
|
The AST will contain a `Comment` node with an `inline: true` property.
|
||
|
|
||
|
### Mixins
|
||
|
|
||
|
Parsing of LESS mixins is supported.
|
||
|
|
||
|
```less
|
||
|
.my-mixin {
|
||
|
color: black;
|
||
|
}
|
||
|
```
|
||
|
|
||
|
The AST will contain an `AtRule` node with a `mixin: true` property.
|
||
|
|
||
|
#### `!important`
|
||
|
|
||
|
Mixins that declare `!important` will contain an `important: true` property on their respective node.
|
||
|
|
||
|
### Variables
|
||
|
|
||
|
Parsing of LESS variables is supported.
|
||
|
|
||
|
```less
|
||
|
@link-color: #428bca;
|
||
|
```
|
||
|
|
||
|
The AST will contain an `AtRule` node with a `variable: true` property.
|
||
|
|
||
|
_Note: LESS variables are strictly parsed - a colon (`:`) must immediately follow a variable name._
|
||
|
|
||
|
## Stringifying
|
||
|
|
||
|
To process LESS code without PostCSS transformations, custom stringifier
|
||
|
should be provided.
|
||
|
|
||
|
```js
|
||
|
const postcss = require('postcss');
|
||
|
const syntax = require('postcss-less');
|
||
|
|
||
|
const less = `
|
||
|
// inline comment
|
||
|
|
||
|
.container {
|
||
|
.mixin-1();
|
||
|
.mixin-2;
|
||
|
.mixin-3 (@width: 100px) {
|
||
|
width: @width;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
.rotation(@deg:5deg){
|
||
|
.transform(rotate(@deg));
|
||
|
}
|
||
|
`;
|
||
|
|
||
|
const result = await postcss().process(less, { syntax });
|
||
|
|
||
|
// will contain the value of `less`
|
||
|
const { content } = result;
|
||
|
```
|
||
|
|
||
|
## Use Cases
|
||
|
|
||
|
- Lint LESS code with 3rd-party plugins.
|
||
|
- Apply PostCSS transformations (such as [Autoprefixer](https://github.com/postcss/autoprefixer)) directly to the LESS source code
|
||
|
|
||
|
## Meta
|
||
|
|
||
|
[CONTRIBUTING](./.github/CONTRIBUTING)
|
||
|
|
||
|
[LICENSE (MIT)](./LICENSE)
|