MediaFeature.js•1.61 kB
import {
Ident,
Number,
Dimension,
LeftParenthesis,
RightParenthesis,
Colon,
Delim
} from '../../tokenizer/index.js';
export const name = 'MediaFeature';
export const structure = {
name: String,
value: ['Identifier', 'Number', 'Dimension', 'Ratio', null]
};
export function parse() {
const start = this.tokenStart;
let name;
let value = null;
this.eat(LeftParenthesis);
this.skipSC();
name = this.consume(Ident);
this.skipSC();
if (this.tokenType !== RightParenthesis) {
this.eat(Colon);
this.skipSC();
switch (this.tokenType) {
case Number:
if (this.lookupNonWSType(1) === Delim) {
value = this.Ratio();
} else {
value = this.Number();
}
break;
case Dimension:
value = this.Dimension();
break;
case Ident:
value = this.Identifier();
break;
default:
this.error('Number, dimension, ratio or identifier is expected');
}
this.skipSC();
}
this.eat(RightParenthesis);
return {
type: 'MediaFeature',
loc: this.getLocation(start, this.tokenStart),
name,
value
};
}
export function generate(node) {
this.token(LeftParenthesis, '(');
this.token(Ident, node.name);
if (node.value !== null) {
this.token(Colon, ':');
this.node(node.value);
}
this.token(RightParenthesis, ')');
}