Write Urdu with LuaTex

Question

I figured out how to write with Arabic fonts

\documentclass[a4paper,11pt]{article}

\usepackage{arabluatex} % for support of arabic fonts
\newfontfamily\arabicfont{Amiri}[Script=Arabic, RawFeature={+anum}]
\begin{document}
    My arabic test
    \arb{تحميل كيبورد عربي للكمبيوتر}
\end{document}

According to the documentation of arabluatex it only support arabic fonts. In chapter 1.1. it refers to arabtex and arabxetex for writing in Urdu or Pashto. Since I'm using lualatex I have some troubles. I didn't find proper samples how typeset with these fonts.

I do NOT need to have a transcript latin letter into the lang - preferably I need to switch it off. I only (?) need to display the input with the proper fonts - and most preferable with the proper typesettings. Is there a sample in which Arabic, Urdu, Pashto or/and Dairi are mixed together and are compilable with lualatex (1.10)

Answer 1

This here should probably work (to really make use of the HarfBuzz Render you need either texlive 2020 or should use the lualatex-dev format):

\documentclass{article}
\usepackage{fontspec}
\usepackage[bidi=basic]{babel}
\babelprovide[import=ur,mapdigits]{urdu}
\babelfont[urdu]{rm}[Renderer=HarfBuzz]{Amiri}


\begin{document}
My urdu test

\selectlanguage{urdu}

    یہ ایک جملہ ہے

\end{document}