lepu-test-platform-web/node_modules/csso/lib/parser/scanner.js

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'use strict';
var TokenType = require('./const.js').TokenType;
var TAB = 9;
var N = 10;
var F = 12;
var R = 13;
var SPACE = 32;
var DOUBLE_QUOTE = 34;
var QUOTE = 39;
var RIGHT_PARENTHESIS = 41;
var STAR = 42;
var SLASH = 47;
var BACK_SLASH = 92;
var UNDERSCORE = 95;
var LEFT_CURLY_BRACE = 123;
var RIGHT_CURLY_BRACE = 125;
var WHITESPACE = 1;
var PUNCTUATOR = 2;
var DIGIT = 3;
var STRING = 4;
var PUNCTUATION = {
9: TokenType.Tab, // '\t'
10: TokenType.Newline, // '\n'
13: TokenType.Newline, // '\r'
32: TokenType.Space, // ' '
33: TokenType.ExclamationMark, // '!'
34: TokenType.QuotationMark, // '"'
35: TokenType.NumberSign, // '#'
36: TokenType.DollarSign, // '$'
37: TokenType.PercentSign, // '%'
38: TokenType.Ampersand, // '&'
39: TokenType.Apostrophe, // '\''
40: TokenType.LeftParenthesis, // '('
41: TokenType.RightParenthesis, // ')'
42: TokenType.Asterisk, // '*'
43: TokenType.PlusSign, // '+'
44: TokenType.Comma, // ','
45: TokenType.HyphenMinus, // '-'
46: TokenType.FullStop, // '.'
47: TokenType.Solidus, // '/'
58: TokenType.Colon, // ':'
59: TokenType.Semicolon, // ';'
60: TokenType.LessThanSign, // '<'
61: TokenType.EqualsSign, // '='
62: TokenType.GreaterThanSign, // '>'
63: TokenType.QuestionMark, // '?'
64: TokenType.CommercialAt, // '@'
91: TokenType.LeftSquareBracket, // '['
93: TokenType.RightSquareBracket, // ']'
94: TokenType.CircumflexAccent, // '^'
95: TokenType.LowLine, // '_'
123: TokenType.LeftCurlyBracket, // '{'
124: TokenType.VerticalLine, // '|'
125: TokenType.RightCurlyBracket, // '}'
126: TokenType.Tilde // '~'
};
var SYMBOL_CATEGORY_LENGTH = Math.max.apply(null, Object.keys(PUNCTUATION)) + 1;
var SYMBOL_CATEGORY = new Uint32Array(SYMBOL_CATEGORY_LENGTH);
var IS_PUNCTUATOR = new Uint32Array(SYMBOL_CATEGORY_LENGTH);
// fill categories
Object.keys(PUNCTUATION).forEach(function(key) {
SYMBOL_CATEGORY[Number(key)] = PUNCTUATOR;
IS_PUNCTUATOR[Number(key)] = PUNCTUATOR;
}, SYMBOL_CATEGORY);
// don't treat as punctuator
IS_PUNCTUATOR[UNDERSCORE] = 0;
for (var i = 48; i <= 57; i++) {
SYMBOL_CATEGORY[i] = DIGIT;
}
SYMBOL_CATEGORY[SPACE] = WHITESPACE;
SYMBOL_CATEGORY[TAB] = WHITESPACE;
SYMBOL_CATEGORY[N] = WHITESPACE;
SYMBOL_CATEGORY[R] = WHITESPACE;
SYMBOL_CATEGORY[F] = WHITESPACE;
SYMBOL_CATEGORY[QUOTE] = STRING;
SYMBOL_CATEGORY[DOUBLE_QUOTE] = STRING;
//
// scanner
//
var Scanner = function(source, initBlockMode, initLine, initColumn) {
this.source = source;
this.pos = source.charCodeAt(0) === 0xFEFF ? 1 : 0;
this.eof = this.pos === this.source.length;
this.line = typeof initLine === 'undefined' ? 1 : initLine;
this.lineStartPos = typeof initColumn === 'undefined' ? -1 : -initColumn;
this.minBlockMode = initBlockMode ? 1 : 0;
this.blockMode = this.minBlockMode;
this.urlMode = false;
this.prevToken = null;
this.token = null;
this.buffer = [];
};
Scanner.prototype = {
lookup: function(offset) {
if (offset === 0) {
return this.token;
}
for (var i = this.buffer.length; !this.eof && i < offset; i++) {
this.buffer.push(this.getToken());
}
return offset <= this.buffer.length ? this.buffer[offset - 1] : null;
},
lookupType: function(offset, type) {
var token = this.lookup(offset);
return token !== null && token.type === type;
},
next: function() {
var newToken = null;
if (this.buffer.length !== 0) {
newToken = this.buffer.shift();
} else if (!this.eof) {
newToken = this.getToken();
}
this.prevToken = this.token;
this.token = newToken;
return newToken;
},
tokenize: function() {
var tokens = [];
for (; this.pos < this.source.length; this.pos++) {
tokens.push(this.getToken());
}
return tokens;
},
getToken: function() {
var code = this.source.charCodeAt(this.pos);
var line = this.line;
var column = this.pos - this.lineStartPos;
var offset = this.pos;
var next;
var type;
var value;
switch (code < SYMBOL_CATEGORY_LENGTH ? SYMBOL_CATEGORY[code] : 0) {
case DIGIT:
type = TokenType.DecimalNumber;
value = this.readDecimalNumber();
break;
case STRING:
type = TokenType.String;
value = this.readString(code);
break;
case WHITESPACE:
type = TokenType.Space;
value = this.readSpaces();
break;
case PUNCTUATOR:
if (code === SLASH) {
next = this.pos + 1 < this.source.length ? this.source.charCodeAt(this.pos + 1) : 0;
if (next === STAR) { // /*
type = TokenType.Comment;
value = this.readComment();
break;
} else if (next === SLASH && !this.urlMode) { // //
if (this.blockMode > 0) {
var skip = 2;
while (this.source.charCodeAt(this.pos + 2) === SLASH) {
skip++;
}
type = TokenType.Identifier;
value = this.readIdentifier(skip);
this.urlMode = this.urlMode || value === 'url';
} else {
type = TokenType.Unknown;
value = this.readUnknown();
}
break;
}
}
type = PUNCTUATION[code];
value = String.fromCharCode(code);
this.pos++;
if (code === RIGHT_PARENTHESIS) {
this.urlMode = false;
} else if (code === LEFT_CURLY_BRACE) {
this.blockMode++;
} else if (code === RIGHT_CURLY_BRACE) {
if (this.blockMode > this.minBlockMode) {
this.blockMode--;
}
}
break;
default:
type = TokenType.Identifier;
value = this.readIdentifier(0);
this.urlMode = this.urlMode || value === 'url';
}
this.eof = this.pos === this.source.length;
return {
type: type,
value: value,
offset: offset,
line: line,
column: column
};
},
isNewline: function(code) {
if (code === N || code === F || code === R) {
if (code === R && this.pos + 1 < this.source.length && this.source.charCodeAt(this.pos + 1) === N) {
this.pos++;
}
this.line++;
this.lineStartPos = this.pos;
return true;
}
return false;
},
readSpaces: function() {
var start = this.pos;
for (; this.pos < this.source.length; this.pos++) {
var code = this.source.charCodeAt(this.pos);
if (!this.isNewline(code) && code !== SPACE && code !== TAB) {
break;
}
}
return this.source.substring(start, this.pos);
},
readComment: function() {
var start = this.pos;
for (this.pos += 2; this.pos < this.source.length; this.pos++) {
var code = this.source.charCodeAt(this.pos);
if (code === STAR) { // */
if (this.source.charCodeAt(this.pos + 1) === SLASH) {
this.pos += 2;
break;
}
} else {
this.isNewline(code);
}
}
return this.source.substring(start, this.pos);
},
readUnknown: function() {
var start = this.pos;
for (this.pos += 2; this.pos < this.source.length; this.pos++) {
if (this.isNewline(this.source.charCodeAt(this.pos), this.source)) {
break;
}
}
return this.source.substring(start, this.pos);
},
readString: function(quote) {
var start = this.pos;
var res = '';
for (this.pos++; this.pos < this.source.length; this.pos++) {
var code = this.source.charCodeAt(this.pos);
if (code === BACK_SLASH) {
var end = this.pos++;
if (this.isNewline(this.source.charCodeAt(this.pos), this.source)) {
res += this.source.substring(start, end);
start = this.pos + 1;
}
} else if (code === quote) {
this.pos++;
break;
}
}
return res + this.source.substring(start, this.pos);
},
readDecimalNumber: function() {
var start = this.pos;
var code;
for (this.pos++; this.pos < this.source.length; this.pos++) {
code = this.source.charCodeAt(this.pos);
if (code < 48 || code > 57) { // 0 .. 9
break;
}
}
return this.source.substring(start, this.pos);
},
readIdentifier: function(skip) {
var start = this.pos;
for (this.pos += skip; this.pos < this.source.length; this.pos++) {
var code = this.source.charCodeAt(this.pos);
if (code === BACK_SLASH) {
this.pos++;
// skip escaped unicode sequence that can ends with space
// [0-9a-f]{1,6}(\r\n|[ \n\r\t\f])?
for (var i = 0; i < 7 && this.pos + i < this.source.length; i++) {
code = this.source.charCodeAt(this.pos + i);
if (i !== 6) {
if ((code >= 48 && code <= 57) || // 0 .. 9
(code >= 65 && code <= 70) || // A .. F
(code >= 97 && code <= 102)) { // a .. f
continue;
}
}
if (i > 0) {
this.pos += i - 1;
if (code === SPACE || code === TAB || this.isNewline(code)) {
this.pos++;
}
}
break;
}
} else if (code < SYMBOL_CATEGORY_LENGTH &&
IS_PUNCTUATOR[code] === PUNCTUATOR) {
break;
}
}
return this.source.substring(start, this.pos);
}
};
// warm up tokenizer to elimitate code branches that never execute
// fix soft deoptimizations (insufficient type feedback)
new Scanner('\n\r\r\n\f//""\'\'/**/1a;.{url(a)}').lookup(1e3);
module.exports = Scanner;