# A bug in fontspec, lua(la)tex, or the Junicode font?

Consider the following MWE:

\documentclass{article}
\usepackage{fontspec}
\setmainfont{Junicode}
\setsansfont[Scale=MatchLowercase]{HelveticaNeue}
\setmonofont[Scale=MatchLowercase]{Consolas}
\begin{document}
\noindent
some ordinary text\newline
{\sffamily some sans-serif text}\newline
{\ttfamily some monospaced text}
\end{document}


On a MacBook running MacTeX2012 and MacOSX 10.7.5, this MWE produces the following output when run under LuaLaTeX:

but the following (and rather more pleasing) output when run under XeLaTeX:

Obviously, something's not working quite right under LuaLaTeX. My question is: Is this a bug (a) caused by an error in implementing the Scale=MatchLowercase option of fontspec/luatex, (b) caused by a poorly-specified parameter in the Junicode font file, or (c) are there two separate bugs at work?

A work-around is to specify [Scale=0.83] for HelveticaNeue and [Scale=0.88] for Consolas. Naturally, though, I'd like to employ a somewhat more automated method to get the scaling of the sans and mono fonts adjusted to the size of the text font.

-
It seems a problem specific to Junicode; with other main fonts it doesn't happen. –  egreg Oct 10 '12 at 19:45
Confirmed with MiKTeX 2.9, and agree with @egreg. This should probably go on sourceforge.net/projects/junicode . –  doncherry Oct 10 '12 at 19:57
There were a similar (or actually the same?) issue with Linux Libertine mentioned here on TeX.sx, but I can’t find it now. If I rememeber correctly, Luatex relies on what is indicated by the font, XeTeX computes the x-height itself. –  Speravir Oct 10 '12 at 20:21
It could be this one: TeX logo with LuaTeX and Linux Biolinum O/G. –  Speravir Oct 10 '12 at 20:25
@doncherry - I've submitted a bug report to the site you listed. –  Mico Oct 10 '12 at 20:59

FontForge has obviously some difficulties to export fonts with "correct" x-height set to be usable with luaotfload. So I'd say it is both a bug in FontForge and luaotfload and it should be fixed in both.