biobulkbende.org/node_modules/css/Readme.md
2020-09-16 14:23:28 +02:00

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# css [![Build Status](https://travis-ci.org/reworkcss/css.svg?branch=master)](https://travis-ci.org/reworkcss/css)
CSS parser / stringifier.
## Installation
$ npm install css
## Usage
```js
var css = require('css');
var obj = css.parse('body { font-size: 12px; }', options);
css.stringify(obj, options);
```
## API
### css.parse(code, [options])
Accepts a CSS string and returns an AST `object`.
`options`:
- silent: silently fail on parse errors.
- source: the path to the file containing `css`. Makes errors and source
maps more helpful, by letting them know where code comes from.
### css.stringify(object, [options])
Accepts an AST `object` (as `css.parse` produces) and returns a CSS string.
`options`:
- indent: the string used to indent the output. Defaults to two spaces.
- compress: omit comments and extraneous whitespace.
- sourcemap: return a sourcemap along with the CSS output. Using the `source`
option of `css.parse` is strongly recommended when creating a source map.
Specify `sourcemap: 'generator'` to return the SourceMapGenerator object
instead of serializing the source map.
- inputSourcemaps: (enabled by default, specify `false` to disable) reads any
source maps referenced by the input files when generating the output source
map. When enabled, file system access may be required for reading the
referenced source maps.
### Example
```js
var ast = css.parse('body { font-size: 12px; }', { source: 'source.css' });
var css = css.stringify(ast);
var result = css.stringify(ast, { sourcemap: true });
result.code // string with CSS
result.map // source map object
```
### Errors
Errors thrown during parsing have the following properties:
- message: `String`. The full error message with the source position.
- reason: `String`. The error message without position.
- filename: `String` or `undefined`. The value of `options.source` if
passed to `css.parse`. Otherwise `undefined`.
- line: `Integer`.
- column: `Integer`.
- source: `String`. The portion of code that couldn't be parsed.
When parsing with the `silent` option, errors are listed in the
`parsingErrors` property of the [`stylesheet`](#stylesheet) node instead
of being thrown.
If you create any errors in plugins such as in
[rework](https://github.com/reworkcss/rework), you __must__ set the same
properties for consistency.
## AST
Interactively explore the AST with <http://iamdustan.com/reworkcss_ast_explorer/>.
### Common properties
All nodes have the following properties.
#### position
Information about the position in the source string that corresponds to
the node.
`Object`:
- start: `Object`:
- line: `Number`.
- column: `Number`.
- end: `Object`:
- line: `Number`.
- column: `Number`.
- source: `String` or `undefined`. The value of `options.source` if passed to
`css.parse`. Otherwise `undefined`.
- content: `String`. The full source string passed to `css.parse`.
The line and column numbers are 1-based: The first line is 1 and the first
column of a line is 1 (not 0).
The `position` property lets you know from which source file the node comes
from (if available), what that file contains, and what part of that file was
parsed into the node.
#### type
`String`. The possible values are the ones listed in the Types section below.
#### parent
A reference to the parent node, or `null` if the node has no parent.
### Types
The available values of `node.type` are listed below, as well as the available
properties of each node (other than the common properties listed above.)
#### stylesheet
The root node returned by `css.parse`.
- stylesheet: `Object`:
- rules: `Array` of nodes with the types `rule`, `comment` and any of the
at-rule types.
- parsingErrors: `Array` of `Error`s. Errors collected during parsing when
option `silent` is true.
#### rule
- selectors: `Array` of `String`s. The list of selectors of the rule, split
on commas. Each selector is trimmed from whitespace and comments.
- declarations: `Array` of nodes with the types `declaration` and `comment`.
#### declaration
- property: `String`. The property name, trimmed from whitespace and
comments. May not be empty.
- value: `String`. The value of the property, trimmed from whitespace and
comments. Empty values are allowed.
#### comment
A rule-level or declaration-level comment. Comments inside selectors,
properties and values etc. are lost.
- comment: `String`. The part between the starting `/*` and the ending `*/`
of the comment, including whitespace.
#### charset
The `@charset` at-rule.
- charset: `String`. The part following `@charset `.
#### custom-media
The `@custom-media` at-rule.
- name: `String`. The `--`-prefixed name.
- media: `String`. The part following the name.
#### document
The `@document` at-rule.
- document: `String`. The part following `@document `.
- vendor: `String` or `undefined`. The vendor prefix in `@document`, or
`undefined` if there is none.
- rules: `Array` of nodes with the types `rule`, `comment` and any of the
at-rule types.
#### font-face
The `@font-face` at-rule.
- declarations: `Array` of nodes with the types `declaration` and `comment`.
#### host
The `@host` at-rule.
- rules: `Array` of nodes with the types `rule`, `comment` and any of the
at-rule types.
#### import
The `@import` at-rule.
- import: `String`. The part following `@import `.
#### keyframes
The `@keyframes` at-rule.
- name: `String`. The name of the keyframes rule.
- vendor: `String` or `undefined`. The vendor prefix in `@keyframes`, or
`undefined` if there is none.
- keyframes: `Array` of nodes with the types `keyframe` and `comment`.
#### keyframe
- values: `Array` of `String`s. The list of “selectors” of the keyframe rule,
split on commas. Each “selector” is trimmed from whitespace.
- declarations: `Array` of nodes with the types `declaration` and `comment`.
#### media
The `@media` at-rule.
- media: `String`. The part following `@media `.
- rules: `Array` of nodes with the types `rule`, `comment` and any of the
at-rule types.
#### namespace
The `@namespace` at-rule.
- namespace: `String`. The part following `@namespace `.
#### page
The `@page` at-rule.
- selectors: `Array` of `String`s. The list of selectors of the rule, split
on commas. Each selector is trimmed from whitespace and comments.
- declarations: `Array` of nodes with the types `declaration` and `comment`.
#### supports
The `@supports` at-rule.
- supports: `String`. The part following `@supports `.
- rules: `Array` of nodes with the types `rule`, `comment` and any of the
at-rule types.
### Example
CSS:
```css
body {
background: #eee;
color: #888;
}
```
Parse tree:
```json
{
"type": "stylesheet",
"stylesheet": {
"rules": [
{
"type": "rule",
"selectors": [
"body"
],
"declarations": [
{
"type": "declaration",
"property": "background",
"value": "#eee",
"position": {
"start": {
"line": 2,
"column": 3
},
"end": {
"line": 2,
"column": 19
}
}
},
{
"type": "declaration",
"property": "color",
"value": "#888",
"position": {
"start": {
"line": 3,
"column": 3
},
"end": {
"line": 3,
"column": 14
}
}
}
],
"position": {
"start": {
"line": 1,
"column": 1
},
"end": {
"line": 4,
"column": 2
}
}
}
]
}
}
```
## License
MIT