| '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; |