# unicode-math: Typesetting upright Greek letters

This MWE should typeset an upright theta as given in section 13.1.2 in unicode-math list of symbols, but the output doesn't show what it is expected. Is there anything wrong or missing here?

\RequirePackage{luatex85}
\documentclass{standalone}
\usepackage[no-math]{fontspec}
\usepackage{unicode-math}
\begin{document}
$\muptheta$
\end{document}

The way this commands are printed depend on the math-style option. E.g.

\RequirePackage{luatex85}
\documentclass{standalone}
\usepackage[no-math,]{fontspec}
\usepackage[math-style=french]{unicode-math}

\begin{document}
$\muptheta\mupTheta \mittheta \mitTheta$
\end{document}

But I don't like this implementation. Like you I expect a command like \math*up*theta to stay upright. Also the dependance on the math-style option (which affects latin and other greek too) means that you are not really free to choose the style you want.

Imho it would be better to have some intermediary command like

\theta --> \mathflextheta --> \mathuptheta or \mathittheta depending on the style.

$\symup{\theta}$