Strange result in ligature with Amiri font

[seloumi]

Description

With Amiri font and Script=Arabic feature I obtain an incorrect result with words like "Scientifique" It appears like this "Scientfiique"

Check/indicate

• [x] Relevant for XeTeX
• [ ] Relevant for LuaTeX
• [ ] Issue tracker has been searched for similar issues?
• [ ] Links to discussion if appropriate

Minimal example demonstrating the issue

\documentclass{article}

\usepackage{fontspec}
\setmainfont[Script=Arabic]{Amiri}

\begin{document}

Scientifique
\qquad
{\addfontfeatures{Script=Latin} Scientifique}

\end{document}

Result

[u-fischer]

Well Script=Arabic is the wrong script to write something in Latin. Beside this I don't think that there is anything fontspec can do here, it is probably a font problem.

[seloumi]

@u-fischer my document is in Arabic and I'm facing the issue when writing some Latin words

[seloumi]

@khaledhosny may be you have an idea ?

[khaledhosny]

That is looks odd but expected, don’t use Script=Arabic for non-Arabic text, it will cause HarfBuzz to do layout from right to left, so it sees if as fi and makes it a ligature.

[khaledhosny]

Nothing here is specific to Amiri, you might not get it with most other fonts because Latin ligature lookups won’t be registered for Arabic script, but Amiri does (not purposefully, but because it simplifies font source).

[seloumi]

@khaledhosny Thanks, so nothing to do here? just change to Script=Latin feature for every Latin words containing if ?

[u-fischer]

Of course, script should be detected automatically, but TeX lives in the previous century and no one gives a damn.

Well luaotfload has a multiscript=auto option:

\documentclass{article}

\usepackage{fontspec}

\begin{document}

\setmainfont[Renderer=HarfBuzz]{Amiri}
Scientifique  یہ ایک جملہ ہے

\setmainfont[Renderer=HarfBuzz,Script=Arabic]{Amiri}
Scientifique  یہ ایک جملہ ہے

\setmainfont[Renderer=HarfBuzz,RawFeature={multiscript=auto}]{Amiri}
Scientifique  یہ ایک جملہ ہے

\end{document}

[jbezos]

And with babel–luatex: https://github.com/latex3/babel/wiki/What's-new-in-babel-3.38 .