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// Copyright 2009 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
/**
* Creates a CSV lines parser.
*/
class CsvParser {
/**
* Converts \x00 and \u0000 escape sequences in the given string.
*
* @param {string} input field.
**/
escapeField(string) {
let nextPos = string.indexOf("\\");
if (nextPos === -1) return string;
let result = string.substring(0, nextPos);
// Escape sequences of the form \x00 and \u0000;
let endPos = string.length;
let pos = 0;
while (nextPos !== -1) {
let escapeIdentifier = string.charAt(nextPos + 1);
pos = nextPos + 2;
if (escapeIdentifier == 'n') {
result += '\n';
nextPos = pos;
} else if (escapeIdentifier == '\\') {
result += '\\';
nextPos = pos;
} else {
if (escapeIdentifier == 'x') {
// \x00 ascii range escapes consume 2 chars.
nextPos = pos + 2;
} else {
// \u0000 unicode range escapes consume 4 chars.
nextPos = pos + 4;
}
// Convert the selected escape sequence to a single character.
let escapeChars = string.substring(pos, nextPos);
result += String.fromCharCode(parseInt(escapeChars, 16));
}
// Continue looking for the next escape sequence.
pos = nextPos;
nextPos = string.indexOf("\\", pos);
// If there are no more escape sequences consume the rest of the string.
if (nextPos === -1) {
result += string.substr(pos);
} else if (pos != nextPos) {
result += string.substring(pos, nextPos);
}
}
return result;
}
/**
* Parses a line of CSV-encoded values. Returns an array of fields.
*
* @param {string} line Input line.
*/
parseLine(line) {
var pos = 0;
var endPos = line.length;
var fields = [];
if (endPos == 0) return fields;
let nextPos = 0;
while(nextPos !== -1) {
nextPos = line.indexOf(',', pos);
let field;
if (nextPos === -1) {
field = line.substr(pos);
} else {
field = line.substring(pos, nextPos);
}
fields.push(this.escapeField(field));
pos = nextPos + 1;
};
return fields
}
}
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