force strings with tabs to be wrapped in quotes

[redchair123]

SheetClip.stringify does not wrap strings that contain tabs but no newlines.

To generate such a monstrosity, set

A1=1&CHAR(9)&2

On Excel 2011 it's displayed as if the tab is a single character, but copying and pasting (pbcopy/pbpaste) reveals that an actual tab character is there!

[warpech]

I don't see tab character in your post above but maybe GitHub stripped it... Would you be able to writes steps to reproduce this error on Handsontable.com?

[redchair123]

Here's one way to show the issue -- admittedly, there is also an issue in parse but this patch focuses just on the stringify part (this is on OSX with excel 2011, but I suspect the same issue exists on linux with libreoffice and windows with excel 2010/2013).

ISSUE IN PARSE

1. copy the text "multi\ttab\ttest" to your clipboard:

$ echo -e "\"multi\ttab\ttest\"" | tee >(pbcopy)
"multi  tab test" <-- those are tabs

2. paste in excel cell A1. On excel 2011 it displays as if the tabstop is 1: http://imgur.com/cpgj8

3. On the grid at handsontable.com, just select (don't edit) and paste in B2: http://imgur.com/AKQ7C

It should dump in one cell but it now dumps in 3

ISSUE IN STRINGIFY

1. copy the text "multi\ttab\ttest" to your clipboard:

$ echo -e "\"multi\ttab\ttest\"" | tee >(pbcopy)
"multi  tab test" <-- those are tabs

2. On the grid at handsontable.com, edit cell A1 and paste: http://imgur.com/Lqyyb

3. Copy from the grid and paste in excel: http://imgur.com/zGNj5

It should dump in 1 cell but in fact dumps in 3

Fixes

The attached commit fixes the stringify half. If you find the approach reasonable I'll also submit a stringify patch.

[warpech]

Hi @Niggler, sorry that I didn't merge the PR so far. Now I see that you have deleted your fork but I am still able to see the changes that you've submitted. I agree this is a valid issue

[warpech]

Did you also have a fix for the "parse" half of the issue?

[redchair123]

I've been investigating further and actually am not happy with the proposed solution. When I fully understand what's going on I'll submit another PR

[warpech]

Thanks! Me too. I've spent whole last day unvestivating Excel and various CSV/TSV libraries to see if they perform better than my code. In places they are better, but still far from good. I've written more about it in issue #3. I would appreciate your help!