You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

171 lines
4.8 KiB

'use strict';
const types = require('../tokenizer/types.cjs');
const PLUSSIGN = 0x002B; // U+002B PLUS SIGN (+)
const HYPHENMINUS = 0x002D; // U+002D HYPHEN-MINUS (-)
const code = (type, value) => {
if (type === types.Delim) {
type = value;
}
if (typeof type === 'string') {
const charCode = type.charCodeAt(0);
return charCode > 0x7F ? 0x8000 : charCode << 8;
}
return type;
};
// https://www.w3.org/TR/css-syntax-3/#serialization
// The only requirement for serialization is that it must "round-trip" with parsing,
// that is, parsing the stylesheet must produce the same data structures as parsing,
// serializing, and parsing again, except for consecutive <whitespace-token>s,
// which may be collapsed into a single token.
const specPairs = [
[types.Ident, types.Ident],
[types.Ident, types.Function],
[types.Ident, types.Url],
[types.Ident, types.BadUrl],
[types.Ident, '-'],
[types.Ident, types.Number],
[types.Ident, types.Percentage],
[types.Ident, types.Dimension],
[types.Ident, types.CDC],
[types.Ident, types.LeftParenthesis],
[types.AtKeyword, types.Ident],
[types.AtKeyword, types.Function],
[types.AtKeyword, types.Url],
[types.AtKeyword, types.BadUrl],
[types.AtKeyword, '-'],
[types.AtKeyword, types.Number],
[types.AtKeyword, types.Percentage],
[types.AtKeyword, types.Dimension],
[types.AtKeyword, types.CDC],
[types.Hash, types.Ident],
[types.Hash, types.Function],
[types.Hash, types.Url],
[types.Hash, types.BadUrl],
[types.Hash, '-'],
[types.Hash, types.Number],
[types.Hash, types.Percentage],
[types.Hash, types.Dimension],
[types.Hash, types.CDC],
[types.Dimension, types.Ident],
[types.Dimension, types.Function],
[types.Dimension, types.Url],
[types.Dimension, types.BadUrl],
[types.Dimension, '-'],
[types.Dimension, types.Number],
[types.Dimension, types.Percentage],
[types.Dimension, types.Dimension],
[types.Dimension, types.CDC],
['#', types.Ident],
['#', types.Function],
['#', types.Url],
['#', types.BadUrl],
['#', '-'],
['#', types.Number],
['#', types.Percentage],
['#', types.Dimension],
['#', types.CDC], // https://github.com/w3c/csswg-drafts/pull/6874
['-', types.Ident],
['-', types.Function],
['-', types.Url],
['-', types.BadUrl],
['-', '-'],
['-', types.Number],
['-', types.Percentage],
['-', types.Dimension],
['-', types.CDC], // https://github.com/w3c/csswg-drafts/pull/6874
[types.Number, types.Ident],
[types.Number, types.Function],
[types.Number, types.Url],
[types.Number, types.BadUrl],
[types.Number, types.Number],
[types.Number, types.Percentage],
[types.Number, types.Dimension],
[types.Number, '%'],
[types.Number, types.CDC], // https://github.com/w3c/csswg-drafts/pull/6874
['@', types.Ident],
['@', types.Function],
['@', types.Url],
['@', types.BadUrl],
['@', '-'],
['@', types.CDC], // https://github.com/w3c/csswg-drafts/pull/6874
['.', types.Number],
['.', types.Percentage],
['.', types.Dimension],
['+', types.Number],
['+', types.Percentage],
['+', types.Dimension],
['/', '*']
];
// validate with scripts/generate-safe
const safePairs = specPairs.concat([
[types.Ident, types.Hash],
[types.Dimension, types.Hash],
[types.Hash, types.Hash],
[types.AtKeyword, types.LeftParenthesis],
[types.AtKeyword, types.String],
[types.AtKeyword, types.Colon],
[types.Percentage, types.Percentage],
[types.Percentage, types.Dimension],
[types.Percentage, types.Function],
[types.Percentage, '-'],
[types.RightParenthesis, types.Ident],
[types.RightParenthesis, types.Function],
[types.RightParenthesis, types.Percentage],
[types.RightParenthesis, types.Dimension],
[types.RightParenthesis, types.Hash],
[types.RightParenthesis, '-']
]);
function createMap(pairs) {
const isWhiteSpaceRequired = new Set(
pairs.map(([prev, next]) => (code(prev) << 16 | code(next)))
);
return function(prevCode, type, value) {
const nextCode = code(type, value);
const nextCharCode = value.charCodeAt(0);
const emitWs =
(nextCharCode === HYPHENMINUS &&
type !== types.Ident &&
type !== types.Function &&
type !== types.CDC) ||
(nextCharCode === PLUSSIGN)
? isWhiteSpaceRequired.has(prevCode << 16 | nextCharCode << 8)
: isWhiteSpaceRequired.has(prevCode << 16 | nextCode);
if (emitWs) {
this.emit(' ', types.WhiteSpace, true);
}
return nextCode;
};
}
const spec = createMap(specPairs);
const safe = createMap(safePairs);
exports.safe = safe;
exports.spec = spec;