var tokenizer = require('../tokenizer');
|
var isIdentifierStart = tokenizer.isIdentifierStart;
|
var isHexDigit = tokenizer.isHexDigit;
|
var isDigit = tokenizer.isDigit;
|
var cmpStr = tokenizer.cmpStr;
|
var consumeNumber = tokenizer.consumeNumber;
|
var TYPE = tokenizer.TYPE;
|
var anPlusB = require('./generic-an-plus-b');
|
var urange = require('./generic-urange');
|
|
var cssWideKeywords = ['unset', 'initial', 'inherit'];
|
var calcFunctionNames = ['calc(', '-moz-calc(', '-webkit-calc('];
|
|
// https://www.w3.org/TR/css-values-3/#lengths
|
var LENGTH = {
|
// absolute length units
|
'px': true,
|
'mm': true,
|
'cm': true,
|
'in': true,
|
'pt': true,
|
'pc': true,
|
'q': true,
|
|
// relative length units
|
'em': true,
|
'ex': true,
|
'ch': true,
|
'rem': true,
|
|
// viewport-percentage lengths
|
'vh': true,
|
'vw': true,
|
'vmin': true,
|
'vmax': true,
|
'vm': true
|
};
|
|
var ANGLE = {
|
'deg': true,
|
'grad': true,
|
'rad': true,
|
'turn': true
|
};
|
|
var TIME = {
|
's': true,
|
'ms': true
|
};
|
|
var FREQUENCY = {
|
'hz': true,
|
'khz': true
|
};
|
|
// https://www.w3.org/TR/css-values-3/#resolution (https://drafts.csswg.org/css-values/#resolution)
|
var RESOLUTION = {
|
'dpi': true,
|
'dpcm': true,
|
'dppx': true,
|
'x': true // https://github.com/w3c/csswg-drafts/issues/461
|
};
|
|
// https://drafts.csswg.org/css-grid/#fr-unit
|
var FLEX = {
|
'fr': true
|
};
|
|
// https://www.w3.org/TR/css3-speech/#mixing-props-voice-volume
|
var DECIBEL = {
|
'db': true
|
};
|
|
// https://www.w3.org/TR/css3-speech/#voice-props-voice-pitch
|
var SEMITONES = {
|
'st': true
|
};
|
|
// safe char code getter
|
function charCode(str, index) {
|
return index < str.length ? str.charCodeAt(index) : 0;
|
}
|
|
function eqStr(actual, expected) {
|
return cmpStr(actual, 0, actual.length, expected);
|
}
|
|
function eqStrAny(actual, expected) {
|
for (var i = 0; i < expected.length; i++) {
|
if (eqStr(actual, expected[i])) {
|
return true;
|
}
|
}
|
|
return false;
|
}
|
|
// IE postfix hack, i.e. 123\0 or 123px\9
|
function isPostfixIeHack(str, offset) {
|
if (offset !== str.length - 2) {
|
return false;
|
}
|
|
return (
|
str.charCodeAt(offset) === 0x005C && // U+005C REVERSE SOLIDUS (\)
|
isDigit(str.charCodeAt(offset + 1))
|
);
|
}
|
|
function outOfRange(opts, value, numEnd) {
|
if (opts && opts.type === 'Range') {
|
var num = Number(
|
numEnd !== undefined && numEnd !== value.length
|
? value.substr(0, numEnd)
|
: value
|
);
|
|
if (isNaN(num)) {
|
return true;
|
}
|
|
if (opts.min !== null && num < opts.min) {
|
return true;
|
}
|
|
if (opts.max !== null && num > opts.max) {
|
return true;
|
}
|
}
|
|
return false;
|
}
|
|
function consumeFunction(token, getNextToken) {
|
var startIdx = token.index;
|
var length = 0;
|
|
// balanced token consuming
|
do {
|
length++;
|
|
if (token.balance <= startIdx) {
|
break;
|
}
|
} while (token = getNextToken(length));
|
|
return length;
|
}
|
|
// TODO: implement
|
// can be used wherever <length>, <frequency>, <angle>, <time>, <percentage>, <number>, or <integer> values are allowed
|
// https://drafts.csswg.org/css-values/#calc-notation
|
function calc(next) {
|
return function(token, getNextToken, opts) {
|
if (token === null) {
|
return 0;
|
}
|
|
if (token.type === TYPE.Function && eqStrAny(token.value, calcFunctionNames)) {
|
return consumeFunction(token, getNextToken);
|
}
|
|
return next(token, getNextToken, opts);
|
};
|
}
|
|
function tokenType(expectedTokenType) {
|
return function(token) {
|
if (token === null || token.type !== expectedTokenType) {
|
return 0;
|
}
|
|
return 1;
|
};
|
}
|
|
function func(name) {
|
name = name + '(';
|
|
return function(token, getNextToken) {
|
if (token !== null && eqStr(token.value, name)) {
|
return consumeFunction(token, getNextToken);
|
}
|
|
return 0;
|
};
|
}
|
|
// =========================
|
// Complex types
|
//
|
|
// https://drafts.csswg.org/css-values-4/#custom-idents
|
// 4.2. Author-defined Identifiers: the <custom-ident> type
|
// Some properties accept arbitrary author-defined identifiers as a component value.
|
// This generic data type is denoted by <custom-ident>, and represents any valid CSS identifier
|
// that would not be misinterpreted as a pre-defined keyword in that property’s value definition.
|
//
|
// See also: https://developer.mozilla.org/en-US/docs/Web/CSS/custom-ident
|
function customIdent(token) {
|
if (token === null || token.type !== TYPE.Ident) {
|
return 0;
|
}
|
|
var name = token.value.toLowerCase();
|
|
// The CSS-wide keywords are not valid <custom-ident>s
|
if (eqStrAny(name, cssWideKeywords)) {
|
return 0;
|
}
|
|
// The default keyword is reserved and is also not a valid <custom-ident>
|
if (eqStr(name, 'default')) {
|
return 0;
|
}
|
|
// TODO: ignore property specific keywords (as described https://developer.mozilla.org/en-US/docs/Web/CSS/custom-ident)
|
// Specifications using <custom-ident> must specify clearly what other keywords
|
// are excluded from <custom-ident>, if any—for example by saying that any pre-defined keywords
|
// in that property’s value definition are excluded. Excluded keywords are excluded
|
// in all ASCII case permutations.
|
|
return 1;
|
}
|
|
// https://drafts.csswg.org/css-variables/#typedef-custom-property-name
|
// A custom property is any property whose name starts with two dashes (U+002D HYPHEN-MINUS), like --foo.
|
// The <custom-property-name> production corresponds to this: it’s defined as any valid identifier
|
// that starts with two dashes, except -- itself, which is reserved for future use by CSS.
|
// NOTE: Current implementation treat `--` as a valid name since most (all?) major browsers treat it as valid.
|
function customPropertyName(token) {
|
// ... defined as any valid identifier
|
if (token === null || token.type !== TYPE.Ident) {
|
return 0;
|
}
|
|
// ... that starts with two dashes (U+002D HYPHEN-MINUS)
|
if (charCode(token.value, 0) !== 0x002D || charCode(token.value, 1) !== 0x002D) {
|
return 0;
|
}
|
|
return 1;
|
}
|
|
// https://drafts.csswg.org/css-color-4/#hex-notation
|
// The syntax of a <hex-color> is a <hash-token> token whose value consists of 3, 4, 6, or 8 hexadecimal digits.
|
// In other words, a hex color is written as a hash character, "#", followed by some number of digits 0-9 or
|
// letters a-f (the case of the letters doesn’t matter - #00ff00 is identical to #00FF00).
|
function hexColor(token) {
|
if (token === null || token.type !== TYPE.Hash) {
|
return 0;
|
}
|
|
var length = token.value.length;
|
|
// valid values (length): #rgb (4), #rgba (5), #rrggbb (7), #rrggbbaa (9)
|
if (length !== 4 && length !== 5 && length !== 7 && length !== 9) {
|
return 0;
|
}
|
|
for (var i = 1; i < length; i++) {
|
if (!isHexDigit(token.value.charCodeAt(i))) {
|
return 0;
|
}
|
}
|
|
return 1;
|
}
|
|
function idSelector(token) {
|
if (token === null || token.type !== TYPE.Hash) {
|
return 0;
|
}
|
|
if (!isIdentifierStart(charCode(token.value, 1), charCode(token.value, 2), charCode(token.value, 3))) {
|
return 0;
|
}
|
|
return 1;
|
}
|
|
// https://drafts.csswg.org/css-syntax/#any-value
|
// It represents the entirety of what a valid declaration can have as its value.
|
function declarationValue(token, getNextToken) {
|
if (!token) {
|
return 0;
|
}
|
|
var length = 0;
|
var level = 0;
|
var startIdx = token.index;
|
|
// The <declaration-value> production matches any sequence of one or more tokens,
|
// so long as the sequence ...
|
scan:
|
do {
|
switch (token.type) {
|
// ... does not contain <bad-string-token>, <bad-url-token>,
|
case TYPE.BadString:
|
case TYPE.BadUrl:
|
break scan;
|
|
// ... unmatched <)-token>, <]-token>, or <}-token>,
|
case TYPE.RightCurlyBracket:
|
case TYPE.RightParenthesis:
|
case TYPE.RightSquareBracket:
|
if (token.balance > token.index || token.balance < startIdx) {
|
break scan;
|
}
|
|
level--;
|
break;
|
|
// ... or top-level <semicolon-token> tokens
|
case TYPE.Semicolon:
|
if (level === 0) {
|
break scan;
|
}
|
|
break;
|
|
// ... or <delim-token> tokens with a value of "!"
|
case TYPE.Delim:
|
if (token.value === '!' && level === 0) {
|
break scan;
|
}
|
|
break;
|
|
case TYPE.Function:
|
case TYPE.LeftParenthesis:
|
case TYPE.LeftSquareBracket:
|
case TYPE.LeftCurlyBracket:
|
level++;
|
break;
|
}
|
|
length++;
|
|
// until balance closing
|
if (token.balance <= startIdx) {
|
break;
|
}
|
} while (token = getNextToken(length));
|
|
return length;
|
}
|
|
// https://drafts.csswg.org/css-syntax/#any-value
|
// The <any-value> production is identical to <declaration-value>, but also
|
// allows top-level <semicolon-token> tokens and <delim-token> tokens
|
// with a value of "!". It represents the entirety of what valid CSS can be in any context.
|
function anyValue(token, getNextToken) {
|
if (!token) {
|
return 0;
|
}
|
|
var startIdx = token.index;
|
var length = 0;
|
|
// The <any-value> production matches any sequence of one or more tokens,
|
// so long as the sequence ...
|
scan:
|
do {
|
switch (token.type) {
|
// ... does not contain <bad-string-token>, <bad-url-token>,
|
case TYPE.BadString:
|
case TYPE.BadUrl:
|
break scan;
|
|
// ... unmatched <)-token>, <]-token>, or <}-token>,
|
case TYPE.RightCurlyBracket:
|
case TYPE.RightParenthesis:
|
case TYPE.RightSquareBracket:
|
if (token.balance > token.index || token.balance < startIdx) {
|
break scan;
|
}
|
|
break;
|
}
|
|
length++;
|
|
// until balance closing
|
if (token.balance <= startIdx) {
|
break;
|
}
|
} while (token = getNextToken(length));
|
|
return length;
|
}
|
|
// =========================
|
// Dimensions
|
//
|
|
function dimension(type) {
|
return function(token, getNextToken, opts) {
|
if (token === null || token.type !== TYPE.Dimension) {
|
return 0;
|
}
|
|
var numberEnd = consumeNumber(token.value, 0);
|
|
// check unit
|
if (type !== null) {
|
// check for IE postfix hack, i.e. 123px\0 or 123px\9
|
var reverseSolidusOffset = token.value.indexOf('\\', numberEnd);
|
var unit = reverseSolidusOffset === -1 || !isPostfixIeHack(token.value, reverseSolidusOffset)
|
? token.value.substr(numberEnd)
|
: token.value.substring(numberEnd, reverseSolidusOffset);
|
|
if (type.hasOwnProperty(unit.toLowerCase()) === false) {
|
return 0;
|
}
|
}
|
|
// check range if specified
|
if (outOfRange(opts, token.value, numberEnd)) {
|
return 0;
|
}
|
|
return 1;
|
};
|
}
|
|
// =========================
|
// Percentage
|
//
|
|
// §5.5. Percentages: the <percentage> type
|
// https://drafts.csswg.org/css-values-4/#percentages
|
function percentage(token, getNextToken, opts) {
|
// ... corresponds to the <percentage-token> production
|
if (token === null || token.type !== TYPE.Percentage) {
|
return 0;
|
}
|
|
// check range if specified
|
if (outOfRange(opts, token.value, token.value.length - 1)) {
|
return 0;
|
}
|
|
return 1;
|
}
|
|
// =========================
|
// Numeric
|
//
|
|
// https://drafts.csswg.org/css-values-4/#numbers
|
// The value <zero> represents a literal number with the value 0. Expressions that merely
|
// evaluate to a <number> with the value 0 (for example, calc(0)) do not match <zero>;
|
// only literal <number-token>s do.
|
function zero(next) {
|
if (typeof next !== 'function') {
|
next = function() {
|
return 0;
|
};
|
}
|
|
return function(token, getNextToken, opts) {
|
if (token !== null && token.type === TYPE.Number) {
|
if (Number(token.value) === 0) {
|
return 1;
|
}
|
}
|
|
return next(token, getNextToken, opts);
|
};
|
}
|
|
// § 5.3. Real Numbers: the <number> type
|
// https://drafts.csswg.org/css-values-4/#numbers
|
// Number values are denoted by <number>, and represent real numbers, possibly with a fractional component.
|
// ... It corresponds to the <number-token> production
|
function number(token, getNextToken, opts) {
|
if (token === null) {
|
return 0;
|
}
|
|
var numberEnd = consumeNumber(token.value, 0);
|
var isNumber = numberEnd === token.value.length;
|
if (!isNumber && !isPostfixIeHack(token.value, numberEnd)) {
|
return 0;
|
}
|
|
// check range if specified
|
if (outOfRange(opts, token.value, numberEnd)) {
|
return 0;
|
}
|
|
return 1;
|
}
|
|
// §5.2. Integers: the <integer> type
|
// https://drafts.csswg.org/css-values-4/#integers
|
function integer(token, getNextToken, opts) {
|
// ... corresponds to a subset of the <number-token> production
|
if (token === null || token.type !== TYPE.Number) {
|
return 0;
|
}
|
|
// The first digit of an integer may be immediately preceded by `-` or `+` to indicate the integer’s sign.
|
var i = token.value.charCodeAt(0) === 0x002B || // U+002B PLUS SIGN (+)
|
token.value.charCodeAt(0) === 0x002D ? 1 : 0; // U+002D HYPHEN-MINUS (-)
|
|
// When written literally, an integer is one or more decimal digits 0 through 9 ...
|
for (; i < token.value.length; i++) {
|
if (!isDigit(token.value.charCodeAt(i))) {
|
return 0;
|
}
|
}
|
|
// check range if specified
|
if (outOfRange(opts, token.value, i)) {
|
return 0;
|
}
|
|
return 1;
|
}
|
|
module.exports = {
|
// token types
|
'ident-token': tokenType(TYPE.Ident),
|
'function-token': tokenType(TYPE.Function),
|
'at-keyword-token': tokenType(TYPE.AtKeyword),
|
'hash-token': tokenType(TYPE.Hash),
|
'string-token': tokenType(TYPE.String),
|
'bad-string-token': tokenType(TYPE.BadString),
|
'url-token': tokenType(TYPE.Url),
|
'bad-url-token': tokenType(TYPE.BadUrl),
|
'delim-token': tokenType(TYPE.Delim),
|
'number-token': tokenType(TYPE.Number),
|
'percentage-token': tokenType(TYPE.Percentage),
|
'dimension-token': tokenType(TYPE.Dimension),
|
'whitespace-token': tokenType(TYPE.WhiteSpace),
|
'CDO-token': tokenType(TYPE.CDO),
|
'CDC-token': tokenType(TYPE.CDC),
|
'colon-token': tokenType(TYPE.Colon),
|
'semicolon-token': tokenType(TYPE.Semicolon),
|
'comma-token': tokenType(TYPE.Comma),
|
'[-token': tokenType(TYPE.LeftSquareBracket),
|
']-token': tokenType(TYPE.RightSquareBracket),
|
'(-token': tokenType(TYPE.LeftParenthesis),
|
')-token': tokenType(TYPE.RightParenthesis),
|
'{-token': tokenType(TYPE.LeftCurlyBracket),
|
'}-token': tokenType(TYPE.RightCurlyBracket),
|
|
// token type aliases
|
'string': tokenType(TYPE.String),
|
'ident': tokenType(TYPE.Ident),
|
|
// complex types
|
'custom-ident': customIdent,
|
'custom-property-name': customPropertyName,
|
'hex-color': hexColor,
|
'id-selector': idSelector, // element( <id-selector> )
|
'an-plus-b': anPlusB,
|
'urange': urange,
|
'declaration-value': declarationValue,
|
'any-value': anyValue,
|
|
// dimensions
|
'dimension': calc(dimension(null)),
|
'angle': calc(dimension(ANGLE)),
|
'decibel': calc(dimension(DECIBEL)),
|
'frequency': calc(dimension(FREQUENCY)),
|
'flex': calc(dimension(FLEX)),
|
'length': calc(zero(dimension(LENGTH))),
|
'resolution': calc(dimension(RESOLUTION)),
|
'semitones': calc(dimension(SEMITONES)),
|
'time': calc(dimension(TIME)),
|
|
// percentage
|
'percentage': calc(percentage),
|
|
// numeric
|
'zero': zero(),
|
'number': calc(number),
|
'integer': calc(integer),
|
|
// old IE stuff
|
'-ms-legacy-expression': func('expression')
|
};
|
