Condition.cjs•3.62 kB
'use strict';
const types = require('../../tokenizer/types.cjs');
const MediaFeatureToken = new Set([types.Colon, types.RightParenthesis, types.EOF]);
const SupportsFeatureToken = new Set([types.Colon, types.EOF]);
const name = 'Condition';
const structure = {
kind: String,
children: [[
'Identifier',
'Feature',
'FeatureRange'
]]
};
const conditions = {
media() {
if (this.tokenType === types.LeftParenthesis) {
const firstToken = this.lookupTypeNonSC(1);
if (firstToken === types.Ident && MediaFeatureToken.has(this.lookupTypeNonSC(2))) {
return this.Feature('media');
} else if (firstToken !== types.LeftParenthesis) {
return this.parseWithFallback(() => this.FeatureRange('media'), (startIndex) => {
this.skip(startIndex - this.tokenIndex);
});
}
}
},
supports() {
if (this.tokenType === types.LeftParenthesis) {
if (this.lookupTypeNonSC(1) === types.Ident && SupportsFeatureToken.has(this.lookupTypeNonSC(2))) {
return this.Declaration();
}
}
},
container() {
if (this.tokenType === types.LeftParenthesis) {
if (this.lookupTypeNonSC(1) === types.Ident && MediaFeatureToken.has(this.lookupTypeNonSC(2))) {
return this.Feature('size');
} else if (this.lookupTypeNonSC(1) !== types.LeftParenthesis) {
return this.FeatureRange('size');
}
}
}
};
function parse(kind = 'media') {
const children = this.createList();
const termParser = conditions[kind];
scan: while (!this.eof) {
switch (this.tokenType) {
case types.Comment:
case types.WhiteSpace:
this.next();
continue;
case types.Ident:
children.push(this.Identifier());
break;
case types.LeftParenthesis: {
let term = termParser.call(this);
if (!term) {
term = this.parseWithFallback(() => {
this.next();
const res = this.Condition(kind);
this.eat(types.RightParenthesis);
return res;
}, (startIndex) => {
this.skip(startIndex - this.tokenIndex);
return this.GeneralEnclosed();
});
}
children.push(term);
break;
}
case types.Function: {
let term = termParser.call(this);
if (!term) {
term = this.GeneralEnclosed();
}
children.push(term);
break;
}
default:
break scan;
}
}
if (children.isEmpty) {
this.error('Condition can\'t be empty');
}
return {
type: 'Condition',
loc: this.getLocationFromList(children),
kind,
children
};
}
function generate(node) {
node.children.forEach(child => {
if (child.type === 'Condition') {
this.token(types.LeftParenthesis, '(');
this.node(child);
this.token(types.RightParenthesis, ')');
} else {
this.node(child);
}
});
}
exports.conditions = conditions;
exports.generate = generate;
exports.name = name;
exports.parse = parse;
exports.structure = structure;