Unbalanced "{" caused by unicode-math line breaks

[choeger]

I do not know if this is a special case for unicode math, but it bugs me that I cannot get rid of these warnings.

\documentclass{article}
\usepackage{unicode-math}

\begin{document}
Test
\end{document}

% latexrun --latex-cmd=lualatex test.tex
test.tex: warning: extra `}' in log; file names may be wrong 
test.tex: warning: extra `}' in log; file names may be wrong 
test.tex: warning: extra `}' in log; file names may be wrong

[choeger]

I did some investigation.

The problem arises from nested braces.

{{foo}} is consumed as follows:

1. { found, rest is: {foo}}
2. search for } and skip over
3. found, rest is } - warn about unbalanced braces

I presume, the same problem occurs in the handling of parenthesis.
I do not know if I will find the time to fix this issue, so this info might be helpful.