'use strict';
|
var uncurryThis = require('../internals/function-uncurry-this');
|
var hasOwn = require('../internals/has-own-property');
|
|
var $SyntaxError = SyntaxError;
|
var $parseInt = parseInt;
|
var fromCharCode = String.fromCharCode;
|
var at = uncurryThis(''.charAt);
|
var slice = uncurryThis(''.slice);
|
var exec = uncurryThis(/./.exec);
|
|
var codePoints = {
|
'\\"': '"',
|
'\\\\': '\\',
|
'\\/': '/',
|
'\\b': '\b',
|
'\\f': '\f',
|
'\\n': '\n',
|
'\\r': '\r',
|
'\\t': '\t'
|
};
|
|
var IS_4_HEX_DIGITS = /^[\da-f]{4}$/i;
|
// eslint-disable-next-line regexp/no-control-character -- safe
|
var IS_C0_CONTROL_CODE = /^[\u0000-\u001F]$/;
|
|
module.exports = function (source, i) {
|
var unterminated = true;
|
var value = '';
|
while (i < source.length) {
|
var chr = at(source, i);
|
if (chr === '\\') {
|
var twoChars = slice(source, i, i + 2);
|
if (hasOwn(codePoints, twoChars)) {
|
value += codePoints[twoChars];
|
i += 2;
|
} else if (twoChars === '\\u') {
|
i += 2;
|
var fourHexDigits = slice(source, i, i + 4);
|
if (!exec(IS_4_HEX_DIGITS, fourHexDigits)) throw new $SyntaxError('Bad Unicode escape at: ' + i);
|
value += fromCharCode($parseInt(fourHexDigits, 16));
|
i += 4;
|
} else throw new $SyntaxError('Unknown escape sequence: "' + twoChars + '"');
|
} else if (chr === '"') {
|
unterminated = false;
|
i++;
|
break;
|
} else {
|
if (exec(IS_C0_CONTROL_CODE, chr)) throw new $SyntaxError('Bad control character in string literal at: ' + i);
|
value += chr;
|
i++;
|
}
|
}
|
if (unterminated) throw new $SyntaxError('Unterminated string at: ' + i);
|
return { value: value, end: i };
|
};
|
