Escape nested quote with an additional quote

According to RFC 4180 the proper way to escape double-quotes in CSV data
is to prepend an additional double-quote character:

> If double-quotes are used to enclose fields, then a double-quote
> appearing inside a field must be escaped by preceding it with
> another double quote.

Currently we escape double-quotes using a backslash. Opening such a file
in Microsoft Excel and/or Apple Numbers breaks the column layout, i.e.
the value containing the double quote is interpretted as multiple
columns instead of one. On the contrary, escaping using an extra
double-quote preserves the expected column layout in both Microsoft
Excel and Apple Numbers.

See also:
 - https://tools.ietf.org/html/rfc4180

Author: eric-thelin

lib/csv-2-json.js

@@ -175,9 +175,8 @@ var splitLine = function (line) {
             stateVariables.parsingValue = true;
             stateVariables.startIndex = index + 1;
         }
-        else if (character === "\\" && charAfter === options.DELIMITER.WRAP && stateVariables.insideWrapDelimiter) {
+        else if (character === options.DELIMITER.WRAP && charAfter === options.DELIMITER.WRAP && stateVariables.insideWrapDelimiter) {
             line = line.slice(0, index) + line.slice(index+1); // Remove the current character from the line
-            index--; // Move to position before to prevent moving ahead and skipping a character
             lastCharacterIndex--; // Update the value since we removed a character
         }
         // Otherwise increment to the next character

lib/json-2-csv.js

@@ -133,7 +133,7 @@ var convertField = function (value) {
     } else if (_.isBoolean(value)) { // If we have a boolean (avoids false being converted to '')
         return options.DELIMITER.WRAP + convertValue(value) + options.DELIMITER.WRAP;
     }
-    value = options.DELIMITER.WRAP && value ? value.replace(new RegExp(options.DELIMITER.WRAP, 'g'), "\\"+options.DELIMITER.WRAP) : value;
+    value = options.DELIMITER.WRAP && value ? value.replace(new RegExp(options.DELIMITER.WRAP, 'g'), options.DELIMITER.WRAP + options.DELIMITER.WRAP) : value;
     return options.DELIMITER.WRAP + convertValue(value) + options.DELIMITER.WRAP; // Otherwise push the current value
 };
 

test/CSV/quoted/nestedQuotes.csv

@@ -1,3 +1,3 @@
 "a string"
 "with a description"
-"with a description and \"quotes\""
+"with a description and ""quotes"""