Zero width non-joiner not working correctly (Bindehemmer arbeitet fehlerhaft)

[Samst Tag]

I recently noticed, that the zero width non-joiner (ZWNJ) does not work correctly (in german language setting).

It is used for separating characters which should not build an ligature automatically. In my example I wanted to use it to separate the ffl-ligature to an f - fl (an ffl-ligature would be wrong in that case).

The first example shows the original Text (notice: The word "aufflog" does not automatically "auf-flog" as it could)

The second example with zero width non-joiner (ZWNJ) breaks the word at the ZWNJ but Publisher "forgets" to insert a hyphen there, which is necessary and to be expected!

The third example is with an zero widh space (ZWSP), that works correctly, allowing to break the word without inserting an automatic hyphen there.

So: It's common to use an ZWNJ to separate two characters to prevent an automatic ligature, but if the word breaks there automatically, a hyphen has to be inserted there automatically (which Publisher doesn't)!

Another problem with the zero-widh spaces: I can't search for words containing them, so if I search for the word "aufflog" in my example text, it only finds one (the first without ZWNJ or ZWSP). Searching for text should ignore that zero-width spaces as they don't change the meaning and appearance of the word, they're just necessary for typographical reasons.

see Wikipedia - ZWNJ and Wikipedia - ZWSP for furher information of using these characters.

 

[MikeTO]

I confirmed this issue. I used the word "difference" in Adobe Garamond Pro with standard ligatures on which gave me an ff ligature. I turned on hyphenation and resized the column so that it broke at f-f. I then inserted a ZWNJ between ff to avoid the ligature but that disabled the automatic hyphenation. This feels like a bug or an unintended limitation to me.

Here's a test file (2.1 beta format).

zwnj.afpub

Hyphenation is off in the left column, on in the right column. The top line of text doesn't have a ZWNJ so there's an auto ligature while the bottom line of text does have a ZWNJ between the ff.

There's a second issue with this that again feels like a bug or an unintended limitation - inserting a ZWNJ breaks spell checking.

[Callum]

Hi,

Apologies but I'm struggling to recreate this likely due to my lack of knowledge in this area. @MikeTO if you have time would you be able to provide steps that I can follow to easily replicate this behaviour using the file you provided?

Thanks
C

[MikeTO]

1 hour ago, Callum said:

Apologies but I'm struggling to recreate this likely due to my lack of knowledge in this area. @MikeTO if you have time would you be able to provide steps that I can follow to easily replicate this behaviour using the file you provided?

Hi Callum, here's a better test file. Just change the width of the divider between the first and second columns to watch how it breaks the word difference. In the first two rows, it will never break because hyphenation is off but I included them for completeness and to show that the ZWNJ breaks spell checking. In the second two rows, it will break at differ-ence but never at dif-ference. The issue is that Publisher is forming the ligature before checking for breaks when it should check for breaks first.

zwnj.afpub

Cheers

[Callum]

Thank you I have now logged this with our devs to be fixed in a future update