Font mixup with Neo Euler and Fontspec

Question

For my document I would like to use Linux Libertine as main font and Neo Euler as maths font. However, there seems to be some conflict with the code I am using. Here is a MWE and its output:

\documentclass{article}

\usepackage{luatextra, amsmath}
\usepackage[math-style=ISO, bold-style=ISO]{unicode-math}

% Main fonts
\defaultfontfeatures{Ligatures=TeX, Scale=MatchLowercase}

\setmainfont[SmallCapsFont={LinLibertineCapitalsO}, SmallCapsFeatures={Letters=SmallCaps}, , Numbers=OldStyle]{Linux Libertine O}
\setsansfont[LetterSpace=3, Numbers={Proportional,OldStyle}]{Myriad Pro}
\setmonofont{Ubuntu Mono}
\setmathfont{Neo Euler}

\begin{document}

\emph{ABCDEFGHIKLMNOPQRSTUVWXZY abcdefghijklmnopqrstuvxyz}
\(ABCDEFGHIKLMNOPQRSTUVWXZY abcdefghijklmnopqrstuvxyz\)
\[ABCDEFGHIKLMNOPQRSTUVWXZY abcdefghijklmnopqrstuvxyz\]
\(1234567890\)
1234567890
\begin{align}
ABCDEFGHIKLMNOPQRSTUVWXZY abcdefghijklmnopqrstuvxyz
\end{align}
\[ \mathbf{\hat{x}} \iiint \mathbf{\dot{A}} \]

\end{document}

Note how there seems to be a mix-up between the two fonts. How can I make sure the correct fonts are selected?

Answer 1

Neo Euler is upright by design and currently math italic slots are empty (now I think this was a bad decision, but no time to fix it now), so [math-style=ISO, bold-style=ISO] does not make much sense here and what you are seeing is the default Computer Modern math font, instead you should use [math-style=upright].