CSS parser / stringifier.
$ npm install css
var css = require('css');
var obj = css.parse('body { font-size: 12px; }', options);
css.stringify(obj, 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.
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
sourceoption ofcss.parseis strongly recommended when creating a source map. Specifysourcemap: 'generator'to return the SourceMapGenerator object instead of serializing the source map. - inputSourcemaps: (enabled by default, specify
falseto 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.
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 objectErrors 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:
Stringorundefined. The value ofoptions.sourceif passed tocss.parse. Otherwiseundefined. - 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 node instead
of being thrown.
If you create any errors in plugins such as in rework, you must set the same properties for consistency.
Interactively explore the AST with http://iamdustan.com/reworkcss_ast_explorer/.
All nodes have the following properties.
Information about the position in the source string that corresponds to the node.
Object:
- start:
Object:- line:
Number. - column:
Number.
- line:
- end:
Object:- line:
Number. - column:
Number.
- line:
- source:
Stringorundefined. The value ofoptions.sourceif passed tocss.parse. Otherwiseundefined. - content:
String. The full source string passed tocss.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.
String. The possible values are the ones listed in the Types section below.
A reference to the parent node, or null if the node has no parent.
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.)
The root node returned by css.parse.
- stylesheet:
Object:- rules:
Arrayof nodes with the typesrule,commentand any of the at-rule types. - parsingErrors:
ArrayofErrors. Errors collected during parsing when optionsilentis true.
- rules:
- selectors:
ArrayofStrings. The list of selectors of the rule, split on commas. Each selector is trimmed from whitespace and comments. - declarations:
Arrayof nodes with the typesdeclarationandcomment.
- 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.
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.
The @charset at-rule.
- charset:
String. The part following@charset.
The @custom-media at-rule.
- name:
String. The---prefixed name. - media:
String. The part following the name.
The @document at-rule.
- document:
String. The part following@document. - vendor:
Stringorundefined. The vendor prefix in@document, orundefinedif there is none. - rules:
Arrayof nodes with the typesrule,commentand any of the at-rule types.
The @font-face at-rule.
- declarations:
Arrayof nodes with the typesdeclarationandcomment.
The @host at-rule.
- rules:
Arrayof nodes with the typesrule,commentand any of the at-rule types.
The @import at-rule.
- import:
String. The part following@import.
The @keyframes at-rule.
- name:
String. The name of the keyframes rule. - vendor:
Stringorundefined. The vendor prefix in@keyframes, orundefinedif there is none. - keyframes:
Arrayof nodes with the typeskeyframeandcomment.
- values:
ArrayofStrings. The list of “selectors” of the keyframe rule, split on commas. Each “selector” is trimmed from whitespace. - declarations:
Arrayof nodes with the typesdeclarationandcomment.
The @media at-rule.
- media:
String. The part following@media. - rules:
Arrayof nodes with the typesrule,commentand any of the at-rule types.
The @namespace at-rule.
- namespace:
String. The part following@namespace.
The @page at-rule.
- selectors:
ArrayofStrings. The list of selectors of the rule, split on commas. Each selector is trimmed from whitespace and comments. - declarations:
Arrayof nodes with the typesdeclarationandcomment.
The @supports at-rule.
- supports:
String. The part following@supports. - rules:
Arrayof nodes with the typesrule,commentand any of the at-rule types.
CSS:
body {
background: #eee;
color: #888;
}Parse tree:
{
"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
}
}
}
]
}
}MIT
