[XeTeX] ZWNJ is being ignored

[Georg Duffner]

Am 2013-04-28 17:57, schrieb Khaled Hosny:
> On Sun, Apr 28, 2013 at 02:56:11PM +0200, Georg Duffner wrote:
>> Hi,
>>
>> I’ve run across a bug in v.0.9999.0 from tlcontrib and I’d like to
>> know if this is still true:
>>
>> XeTeX 0.9999.0 ignores uni200C (zero width non joiner) with latin
>> script. It is needed for inhibiting ligatures at certain places in
>> german. Babel provides a shorthand for this purpose ("|) which
>> inserts a tiny kern between the two letters but that prevents
>> contextual lookups. If I insert a ZWNJ at that place, the ligature
>> substitution takes place nevertheless.
>
> If I use my installed version of EB Garamond (0.014e) ZWNJ works as
> expected, switching to the you linked causes it be ignored, so my guess
> is that you changed something in the font that is causing HarfBuzz to
> ignore the ZWNJ.
>
> Reading the description here, I think it is the use of contextual
> substitution for f-ligatures that is causing ZWNJ to be ignored.
> http://cgit.freedesktop.org/harfbuzz/commit/?id=607feb7cff0e50f8738d2e49ca463fc9d7d494de
>
> That is different from Uniscribe behaviour, so I guess you should raise
> the issue with HarfBuzz developers.

Are you sure?
In Firefox v.20 (not 21 as I wrote before) it gets rendered correctly 
(and in Fontforge it does so too). But I’ll check my lookups again later.

Best regards,
Georg