591 lines
23 KiB
JavaScript
591 lines
23 KiB
JavaScript
var TokenStream = require('../common/TokenStream');
|
||
var adoptBuffer = require('../common/adopt-buffer');
|
||
|
||
var constants = require('./const');
|
||
var TYPE = constants.TYPE;
|
||
|
||
var charCodeDefinitions = require('./char-code-definitions');
|
||
var isNewline = charCodeDefinitions.isNewline;
|
||
var isName = charCodeDefinitions.isName;
|
||
var isValidEscape = charCodeDefinitions.isValidEscape;
|
||
var isNumberStart = charCodeDefinitions.isNumberStart;
|
||
var isIdentifierStart = charCodeDefinitions.isIdentifierStart;
|
||
var charCodeCategory = charCodeDefinitions.charCodeCategory;
|
||
var isBOM = charCodeDefinitions.isBOM;
|
||
|
||
var utils = require('./utils');
|
||
var cmpStr = utils.cmpStr;
|
||
var getNewlineLength = utils.getNewlineLength;
|
||
var findWhiteSpaceEnd = utils.findWhiteSpaceEnd;
|
||
var consumeEscaped = utils.consumeEscaped;
|
||
var consumeName = utils.consumeName;
|
||
var consumeNumber = utils.consumeNumber;
|
||
var consumeBadUrlRemnants = utils.consumeBadUrlRemnants;
|
||
|
||
var OFFSET_MASK = 0x00FFFFFF;
|
||
var TYPE_SHIFT = 24;
|
||
|
||
function tokenize(source, stream) {
|
||
function getCharCode(offset) {
|
||
return offset < sourceLength ? source.charCodeAt(offset) : 0;
|
||
}
|
||
|
||
// § 4.3.3. Consume a numeric token
|
||
function consumeNumericToken() {
|
||
// Consume a number and let number be the result.
|
||
offset = consumeNumber(source, offset);
|
||
|
||
// If the next 3 input code points would start an identifier, then:
|
||
if (isIdentifierStart(getCharCode(offset), getCharCode(offset + 1), getCharCode(offset + 2))) {
|
||
// Create a <dimension-token> with the same value and type flag as number, and a unit set initially to the empty string.
|
||
// Consume a name. Set the <dimension-token>’s unit to the returned value.
|
||
// Return the <dimension-token>.
|
||
type = TYPE.Dimension;
|
||
offset = consumeName(source, offset);
|
||
return;
|
||
}
|
||
|
||
// Otherwise, if the next input code point is U+0025 PERCENTAGE SIGN (%), consume it.
|
||
if (getCharCode(offset) === 0x0025) {
|
||
// Create a <percentage-token> with the same value as number, and return it.
|
||
type = TYPE.Percentage;
|
||
offset++;
|
||
return;
|
||
}
|
||
|
||
// Otherwise, create a <number-token> with the same value and type flag as number, and return it.
|
||
type = TYPE.Number;
|
||
}
|
||
|
||
// § 4.3.4. Consume an ident-like token
|
||
function consumeIdentLikeToken() {
|
||
const nameStartOffset = offset;
|
||
|
||
// Consume a name, and let string be the result.
|
||
offset = consumeName(source, offset);
|
||
|
||
// If string’s value is an ASCII case-insensitive match for "url",
|
||
// and the next input code point is U+0028 LEFT PARENTHESIS ((), consume it.
|
||
if (cmpStr(source, nameStartOffset, offset, 'url') && getCharCode(offset) === 0x0028) {
|
||
// While the next two input code points are whitespace, consume the next input code point.
|
||
offset = findWhiteSpaceEnd(source, offset + 1);
|
||
|
||
// If the next one or two input code points are U+0022 QUOTATION MARK ("), U+0027 APOSTROPHE ('),
|
||
// or whitespace followed by U+0022 QUOTATION MARK (") or U+0027 APOSTROPHE ('),
|
||
// then create a <function-token> with its value set to string and return it.
|
||
if (getCharCode(offset) === 0x0022 ||
|
||
getCharCode(offset) === 0x0027) {
|
||
type = TYPE.Function;
|
||
offset = nameStartOffset + 4;
|
||
return;
|
||
}
|
||
|
||
// Otherwise, consume a url token, and return it.
|
||
consumeUrlToken();
|
||
return;
|
||
}
|
||
|
||
// Otherwise, if the next input code point is U+0028 LEFT PARENTHESIS ((), consume it.
|
||
// Create a <function-token> with its value set to string and return it.
|
||
if (getCharCode(offset) === 0x0028) {
|
||
type = TYPE.Function;
|
||
offset++;
|
||
return;
|
||
}
|
||
|
||
// Otherwise, create an <ident-token> with its value set to string and return it.
|
||
type = TYPE.Ident;
|
||
}
|
||
|
||
// § 4.3.5. Consume a string token
|
||
function consumeStringToken(endingCodePoint) {
|
||
// This algorithm may be called with an ending code point, which denotes the code point
|
||
// that ends the string. If an ending code point is not specified,
|
||
// the current input code point is used.
|
||
if (!endingCodePoint) {
|
||
endingCodePoint = getCharCode(offset++);
|
||
}
|
||
|
||
// Initially create a <string-token> with its value set to the empty string.
|
||
type = TYPE.String;
|
||
|
||
// Repeatedly consume the next input code point from the stream:
|
||
for (; offset < source.length; offset++) {
|
||
var code = source.charCodeAt(offset);
|
||
|
||
switch (charCodeCategory(code)) {
|
||
// ending code point
|
||
case endingCodePoint:
|
||
// Return the <string-token>.
|
||
offset++;
|
||
return;
|
||
|
||
// EOF
|
||
case charCodeCategory.Eof:
|
||
// This is a parse error. Return the <string-token>.
|
||
return;
|
||
|
||
// newline
|
||
case charCodeCategory.WhiteSpace:
|
||
if (isNewline(code)) {
|
||
// This is a parse error. Reconsume the current input code point,
|
||
// create a <bad-string-token>, and return it.
|
||
offset += getNewlineLength(source, offset, code);
|
||
type = TYPE.BadString;
|
||
return;
|
||
}
|
||
break;
|
||
|
||
// U+005C REVERSE SOLIDUS (\)
|
||
case 0x005C:
|
||
// If the next input code point is EOF, do nothing.
|
||
if (offset === source.length - 1) {
|
||
break;
|
||
}
|
||
|
||
var nextCode = getCharCode(offset + 1);
|
||
|
||
// Otherwise, if the next input code point is a newline, consume it.
|
||
if (isNewline(nextCode)) {
|
||
offset += getNewlineLength(source, offset + 1, nextCode);
|
||
} else if (isValidEscape(code, nextCode)) {
|
||
// Otherwise, (the stream starts with a valid escape) consume
|
||
// an escaped code point and append the returned code point to
|
||
// the <string-token>’s value.
|
||
offset = consumeEscaped(source, offset) - 1;
|
||
}
|
||
break;
|
||
|
||
// anything else
|
||
// Append the current input code point to the <string-token>’s value.
|
||
}
|
||
}
|
||
}
|
||
|
||
// § 4.3.6. Consume a url token
|
||
// Note: This algorithm assumes that the initial "url(" has already been consumed.
|
||
// This algorithm also assumes that it’s being called to consume an "unquoted" value, like url(foo).
|
||
// A quoted value, like url("foo"), is parsed as a <function-token>. Consume an ident-like token
|
||
// automatically handles this distinction; this algorithm shouldn’t be called directly otherwise.
|
||
function consumeUrlToken() {
|
||
// Initially create a <url-token> with its value set to the empty string.
|
||
type = TYPE.Url;
|
||
|
||
// Consume as much whitespace as possible.
|
||
offset = findWhiteSpaceEnd(source, offset);
|
||
|
||
// Repeatedly consume the next input code point from the stream:
|
||
for (; offset < source.length; offset++) {
|
||
var code = source.charCodeAt(offset);
|
||
|
||
switch (charCodeCategory(code)) {
|
||
// U+0029 RIGHT PARENTHESIS ())
|
||
case 0x0029:
|
||
// Return the <url-token>.
|
||
offset++;
|
||
return;
|
||
|
||
// EOF
|
||
case charCodeCategory.Eof:
|
||
// This is a parse error. Return the <url-token>.
|
||
return;
|
||
|
||
// whitespace
|
||
case charCodeCategory.WhiteSpace:
|
||
// Consume as much whitespace as possible.
|
||
offset = findWhiteSpaceEnd(source, offset);
|
||
|
||
// If the next input code point is U+0029 RIGHT PARENTHESIS ()) or EOF,
|
||
// consume it and return the <url-token>
|
||
// (if EOF was encountered, this is a parse error);
|
||
if (getCharCode(offset) === 0x0029 || offset >= source.length) {
|
||
if (offset < source.length) {
|
||
offset++;
|
||
}
|
||
return;
|
||
}
|
||
|
||
// otherwise, consume the remnants of a bad url, create a <bad-url-token>,
|
||
// and return it.
|
||
offset = consumeBadUrlRemnants(source, offset);
|
||
type = TYPE.BadUrl;
|
||
return;
|
||
|
||
// U+0022 QUOTATION MARK (")
|
||
// U+0027 APOSTROPHE (')
|
||
// U+0028 LEFT PARENTHESIS (()
|
||
// non-printable code point
|
||
case 0x0022:
|
||
case 0x0027:
|
||
case 0x0028:
|
||
case charCodeCategory.NonPrintable:
|
||
// This is a parse error. Consume the remnants of a bad url,
|
||
// create a <bad-url-token>, and return it.
|
||
offset = consumeBadUrlRemnants(source, offset);
|
||
type = TYPE.BadUrl;
|
||
return;
|
||
|
||
// U+005C REVERSE SOLIDUS (\)
|
||
case 0x005C:
|
||
// If the stream starts with a valid escape, consume an escaped code point and
|
||
// append the returned code point to the <url-token>’s value.
|
||
if (isValidEscape(code, getCharCode(offset + 1))) {
|
||
offset = consumeEscaped(source, offset) - 1;
|
||
break;
|
||
}
|
||
|
||
// Otherwise, this is a parse error. Consume the remnants of a bad url,
|
||
// create a <bad-url-token>, and return it.
|
||
offset = consumeBadUrlRemnants(source, offset);
|
||
type = TYPE.BadUrl;
|
||
return;
|
||
|
||
// anything else
|
||
// Append the current input code point to the <url-token>’s value.
|
||
}
|
||
}
|
||
}
|
||
|
||
if (!stream) {
|
||
stream = new TokenStream();
|
||
}
|
||
|
||
// ensure source is a string
|
||
source = String(source || '');
|
||
|
||
var sourceLength = source.length;
|
||
var offsetAndType = adoptBuffer(stream.offsetAndType, sourceLength + 1); // +1 because of eof-token
|
||
var balance = adoptBuffer(stream.balance, sourceLength + 1);
|
||
var tokenCount = 0;
|
||
var start = isBOM(getCharCode(0));
|
||
var offset = start;
|
||
var balanceCloseType = 0;
|
||
var balanceStart = 0;
|
||
var balancePrev = 0;
|
||
|
||
// https://drafts.csswg.org/css-syntax-3/#consume-token
|
||
// § 4.3.1. Consume a token
|
||
while (offset < sourceLength) {
|
||
var code = source.charCodeAt(offset);
|
||
var type = 0;
|
||
|
||
balance[tokenCount] = sourceLength;
|
||
|
||
switch (charCodeCategory(code)) {
|
||
// whitespace
|
||
case charCodeCategory.WhiteSpace:
|
||
// Consume as much whitespace as possible. Return a <whitespace-token>.
|
||
type = TYPE.WhiteSpace;
|
||
offset = findWhiteSpaceEnd(source, offset + 1);
|
||
break;
|
||
|
||
// U+0022 QUOTATION MARK (")
|
||
case 0x0022:
|
||
// Consume a string token and return it.
|
||
consumeStringToken();
|
||
break;
|
||
|
||
// U+0023 NUMBER SIGN (#)
|
||
case 0x0023:
|
||
// If the next input code point is a name code point or the next two input code points are a valid escape, then:
|
||
if (isName(getCharCode(offset + 1)) || isValidEscape(getCharCode(offset + 1), getCharCode(offset + 2))) {
|
||
// Create a <hash-token>.
|
||
type = TYPE.Hash;
|
||
|
||
// If the next 3 input code points would start an identifier, set the <hash-token>’s type flag to "id".
|
||
// if (isIdentifierStart(getCharCode(offset + 1), getCharCode(offset + 2), getCharCode(offset + 3))) {
|
||
// // TODO: set id flag
|
||
// }
|
||
|
||
// Consume a name, and set the <hash-token>’s value to the returned string.
|
||
offset = consumeName(source, offset + 1);
|
||
|
||
// Return the <hash-token>.
|
||
} else {
|
||
// Otherwise, return a <delim-token> with its value set to the current input code point.
|
||
type = TYPE.Delim;
|
||
offset++;
|
||
}
|
||
|
||
break;
|
||
|
||
// U+0027 APOSTROPHE (')
|
||
case 0x0027:
|
||
// Consume a string token and return it.
|
||
consumeStringToken();
|
||
break;
|
||
|
||
// U+0028 LEFT PARENTHESIS (()
|
||
case 0x0028:
|
||
// Return a <(-token>.
|
||
type = TYPE.LeftParenthesis;
|
||
offset++;
|
||
break;
|
||
|
||
// U+0029 RIGHT PARENTHESIS ())
|
||
case 0x0029:
|
||
// Return a <)-token>.
|
||
type = TYPE.RightParenthesis;
|
||
offset++;
|
||
break;
|
||
|
||
// U+002B PLUS SIGN (+)
|
||
case 0x002B:
|
||
// If the input stream starts with a number, ...
|
||
if (isNumberStart(code, getCharCode(offset + 1), getCharCode(offset + 2))) {
|
||
// ... reconsume the current input code point, consume a numeric token, and return it.
|
||
consumeNumericToken();
|
||
} else {
|
||
// Otherwise, return a <delim-token> with its value set to the current input code point.
|
||
type = TYPE.Delim;
|
||
offset++;
|
||
}
|
||
break;
|
||
|
||
// U+002C COMMA (,)
|
||
case 0x002C:
|
||
// Return a <comma-token>.
|
||
type = TYPE.Comma;
|
||
offset++;
|
||
break;
|
||
|
||
// U+002D HYPHEN-MINUS (-)
|
||
case 0x002D:
|
||
// If the input stream starts with a number, reconsume the current input code point, consume a numeric token, and return it.
|
||
if (isNumberStart(code, getCharCode(offset + 1), getCharCode(offset + 2))) {
|
||
consumeNumericToken();
|
||
} else {
|
||
// Otherwise, if the next 2 input code points are U+002D HYPHEN-MINUS U+003E GREATER-THAN SIGN (->), consume them and return a <CDC-token>.
|
||
if (getCharCode(offset + 1) === 0x002D &&
|
||
getCharCode(offset + 2) === 0x003E) {
|
||
type = TYPE.CDC;
|
||
offset = offset + 3;
|
||
} else {
|
||
// Otherwise, if the input stream starts with an identifier, ...
|
||
if (isIdentifierStart(code, getCharCode(offset + 1), getCharCode(offset + 2))) {
|
||
// ... reconsume the current input code point, consume an ident-like token, and return it.
|
||
consumeIdentLikeToken();
|
||
} else {
|
||
// Otherwise, return a <delim-token> with its value set to the current input code point.
|
||
type = TYPE.Delim;
|
||
offset++;
|
||
}
|
||
}
|
||
}
|
||
break;
|
||
|
||
// U+002E FULL STOP (.)
|
||
case 0x002E:
|
||
// If the input stream starts with a number, ...
|
||
if (isNumberStart(code, getCharCode(offset + 1), getCharCode(offset + 2))) {
|
||
// ... reconsume the current input code point, consume a numeric token, and return it.
|
||
consumeNumericToken();
|
||
} else {
|
||
// Otherwise, return a <delim-token> with its value set to the current input code point.
|
||
type = TYPE.Delim;
|
||
offset++;
|
||
}
|
||
|
||
break;
|
||
|
||
// U+002F SOLIDUS (/)
|
||
case 0x002F:
|
||
// If the next two input code point are U+002F SOLIDUS (/) followed by a U+002A ASTERISK (*),
|
||
if (getCharCode(offset + 1) === 0x002A) {
|
||
// ... consume them and all following code points up to and including the first U+002A ASTERISK (*)
|
||
// followed by a U+002F SOLIDUS (/), or up to an EOF code point.
|
||
type = TYPE.Comment;
|
||
offset = source.indexOf('*/', offset + 2) + 2;
|
||
if (offset === 1) {
|
||
offset = source.length;
|
||
}
|
||
} else {
|
||
type = TYPE.Delim;
|
||
offset++;
|
||
}
|
||
break;
|
||
|
||
// U+003A COLON (:)
|
||
case 0x003A:
|
||
// Return a <colon-token>.
|
||
type = TYPE.Colon;
|
||
offset++;
|
||
break;
|
||
|
||
// U+003B SEMICOLON (;)
|
||
case 0x003B:
|
||
// Return a <semicolon-token>.
|
||
type = TYPE.Semicolon;
|
||
offset++;
|
||
break;
|
||
|
||
// U+003C LESS-THAN SIGN (<)
|
||
case 0x003C:
|
||
// If the next 3 input code points are U+0021 EXCLAMATION MARK U+002D HYPHEN-MINUS U+002D HYPHEN-MINUS (!--), ...
|
||
if (getCharCode(offset + 1) === 0x0021 &&
|
||
getCharCode(offset + 2) === 0x002D &&
|
||
getCharCode(offset + 3) === 0x002D) {
|
||
// ... consume them and return a <CDO-token>.
|
||
type = TYPE.CDO;
|
||
offset = offset + 4;
|
||
} else {
|
||
// Otherwise, return a <delim-token> with its value set to the current input code point.
|
||
type = TYPE.Delim;
|
||
offset++;
|
||
}
|
||
|
||
break;
|
||
|
||
// U+0040 COMMERCIAL AT (@)
|
||
case 0x0040:
|
||
// If the next 3 input code points would start an identifier, ...
|
||
if (isIdentifierStart(getCharCode(offset + 1), getCharCode(offset + 2), getCharCode(offset + 3))) {
|
||
// ... consume a name, create an <at-keyword-token> with its value set to the returned value, and return it.
|
||
type = TYPE.AtKeyword;
|
||
offset = consumeName(source, offset + 1);
|
||
} else {
|
||
// Otherwise, return a <delim-token> with its value set to the current input code point.
|
||
type = TYPE.Delim;
|
||
offset++;
|
||
}
|
||
|
||
break;
|
||
|
||
// U+005B LEFT SQUARE BRACKET ([)
|
||
case 0x005B:
|
||
// Return a <[-token>.
|
||
type = TYPE.LeftSquareBracket;
|
||
offset++;
|
||
break;
|
||
|
||
// U+005C REVERSE SOLIDUS (\)
|
||
case 0x005C:
|
||
// If the input stream starts with a valid escape, ...
|
||
if (isValidEscape(code, getCharCode(offset + 1))) {
|
||
// ... reconsume the current input code point, consume an ident-like token, and return it.
|
||
consumeIdentLikeToken();
|
||
} else {
|
||
// Otherwise, this is a parse error. Return a <delim-token> with its value set to the current input code point.
|
||
type = TYPE.Delim;
|
||
offset++;
|
||
}
|
||
break;
|
||
|
||
// U+005D RIGHT SQUARE BRACKET (])
|
||
case 0x005D:
|
||
// Return a <]-token>.
|
||
type = TYPE.RightSquareBracket;
|
||
offset++;
|
||
break;
|
||
|
||
// U+007B LEFT CURLY BRACKET ({)
|
||
case 0x007B:
|
||
// Return a <{-token>.
|
||
type = TYPE.LeftCurlyBracket;
|
||
offset++;
|
||
break;
|
||
|
||
// U+007D RIGHT CURLY BRACKET (})
|
||
case 0x007D:
|
||
// Return a <}-token>.
|
||
type = TYPE.RightCurlyBracket;
|
||
offset++;
|
||
break;
|
||
|
||
// digit
|
||
case charCodeCategory.Digit:
|
||
// Reconsume the current input code point, consume a numeric token, and return it.
|
||
consumeNumericToken();
|
||
break;
|
||
|
||
// name-start code point
|
||
case charCodeCategory.NameStart:
|
||
// Reconsume the current input code point, consume an ident-like token, and return it.
|
||
consumeIdentLikeToken();
|
||
break;
|
||
|
||
// EOF
|
||
case charCodeCategory.Eof:
|
||
// Return an <EOF-token>.
|
||
break;
|
||
|
||
// anything else
|
||
default:
|
||
// Return a <delim-token> with its value set to the current input code point.
|
||
type = TYPE.Delim;
|
||
offset++;
|
||
}
|
||
|
||
switch (type) {
|
||
case balanceCloseType:
|
||
balancePrev = balanceStart & OFFSET_MASK;
|
||
balanceStart = balance[balancePrev];
|
||
balanceCloseType = balanceStart >> TYPE_SHIFT;
|
||
balance[tokenCount] = balancePrev;
|
||
balance[balancePrev++] = tokenCount;
|
||
for (; balancePrev < tokenCount; balancePrev++) {
|
||
if (balance[balancePrev] === sourceLength) {
|
||
balance[balancePrev] = tokenCount;
|
||
}
|
||
}
|
||
break;
|
||
|
||
case TYPE.LeftParenthesis:
|
||
case TYPE.Function:
|
||
balance[tokenCount] = balanceStart;
|
||
balanceCloseType = TYPE.RightParenthesis;
|
||
balanceStart = (balanceCloseType << TYPE_SHIFT) | tokenCount;
|
||
break;
|
||
|
||
case TYPE.LeftSquareBracket:
|
||
balance[tokenCount] = balanceStart;
|
||
balanceCloseType = TYPE.RightSquareBracket;
|
||
balanceStart = (balanceCloseType << TYPE_SHIFT) | tokenCount;
|
||
break;
|
||
|
||
case TYPE.LeftCurlyBracket:
|
||
balance[tokenCount] = balanceStart;
|
||
balanceCloseType = TYPE.RightCurlyBracket;
|
||
balanceStart = (balanceCloseType << TYPE_SHIFT) | tokenCount;
|
||
break;
|
||
}
|
||
|
||
offsetAndType[tokenCount++] = (type << TYPE_SHIFT) | offset;
|
||
}
|
||
|
||
// finalize buffers
|
||
offsetAndType[tokenCount] = (TYPE.EOF << TYPE_SHIFT) | offset; // <EOF-token>
|
||
balance[tokenCount] = sourceLength;
|
||
balance[sourceLength] = sourceLength; // prevents false positive balance match with any token
|
||
while (balanceStart !== 0) {
|
||
balancePrev = balanceStart & OFFSET_MASK;
|
||
balanceStart = balance[balancePrev];
|
||
balance[balancePrev] = sourceLength;
|
||
}
|
||
|
||
// update stream
|
||
stream.source = source;
|
||
stream.firstCharOffset = start;
|
||
stream.offsetAndType = offsetAndType;
|
||
stream.tokenCount = tokenCount;
|
||
stream.balance = balance;
|
||
stream.reset();
|
||
stream.next();
|
||
|
||
return stream;
|
||
}
|
||
|
||
// extend tokenizer with constants
|
||
Object.keys(constants).forEach(function(key) {
|
||
tokenize[key] = constants[key];
|
||
});
|
||
|
||
// extend tokenizer with static methods from utils
|
||
Object.keys(charCodeDefinitions).forEach(function(key) {
|
||
tokenize[key] = charCodeDefinitions[key];
|
||
});
|
||
Object.keys(utils).forEach(function(key) {
|
||
tokenize[key] = utils[key];
|
||
});
|
||
|
||
module.exports = tokenize;
|