Guess Delimiter Length Limit

[janisdd]

If I understand the code correctly, the preview is used to limit the delimiter guessing to the first 10 lines https://github.com/mholt/PapaParse/blob/master/papaparse.js#L1304

In some situations the data can be very long or wrong formatted (e.g. new line characters are inside quotes...) and sometimes the delimiter is never found (so all data has to be parsed, for every delimiter we guess).

What would be helpful if we could set the max length the guess-delimiter function "looks" ahead, e.g. only 5000 characters (or the 10 rows, the min of both).

This could potentially solve some issues:

• #878
• #861