Font warnings with lualatex-dev on Texlive

[callegar]

Description

Trying lualatex-dev on TeXlive, that is luahbtex 1.11.2 with the pre-release latex format, that is LaTeX2e <2020-02-01> pre-release-3 (develop 2020-1-27 branch), I am getting a lot of font warnings, all of them related to bx series, on documents that compile with no warning with the regular lualatex 1.10.0 with the latex format <2019-10-01> patch level 3.

Specifically I see lots of entries like

LaTeX Font Warning: Font shape `TU/STEP(0)/bx/n' undefined
(Font)              using `TU/STEP(0)/b/n' instead on input line 1111

The issue seems to be triggered by the instancing of all the font series to modify the spacing as IEEEtran.cls does.

Check/indicate

• [ ] Relevant for XeTeX
• [ X] Relevant for LuaTeX
• [ X] Issue tracker has been searched for similar issues?
• [ ] Links to discussion if appropriate

Minimal example demonstrating the issue

The example below uses the article class, incorporating the font spacing logic from IEEEtran

\documentclass{article}
\makeatletter
\newdimen\@IEEEtrantmpdimenA
\newdimen\@IEEEtrantmpdimenB
\newdimen\@IEEEtrantmpdimenC

\def\@IEEEinterspaceratioM{0.35}
\def\@IEEEinterspaceMINratioM{0.23}
\def\@IEEEinterspaceMAXratioM{0.50}

\def\@IEEEinterspaceratioB{0.375}
\def\@IEEEinterspaceMINratioB{0.23}
\def\@IEEEinterspaceMAXratioB{0.55}

\def\@@@IEEEsetfontdimens#1#2#3{{%
    \setlength{\@IEEEtrantmpdimenB}{\f@size pt}
    % grab the font size in pt, could use 1em instead.
    \setlength{\@IEEEtrantmpdimenA}{#1\@IEEEtrantmpdimenB}%
    \fontdimen2\font=\@IEEEtrantmpdimenA\relax
    \addtolength{\@IEEEtrantmpdimenA}{-#2\@IEEEtrantmpdimenB}%
    \fontdimen3\font=-\@IEEEtrantmpdimenA\relax
    \setlength{\@IEEEtrantmpdimenA}{#1\@IEEEtrantmpdimenB}%
    \addtolength{\@IEEEtrantmpdimenA}{-#3\@IEEEtrantmpdimenB}%
    \fontdimen4\font=\@IEEEtrantmpdimenA\relax}}

% revise the interword spacing for each font weight
\def\@@IEEEsetfontdimens{{%
    \mdseries
    \@@@IEEEsetfontdimens{\@IEEEinterspaceratioM}{\@IEEEinterspaceMAXratioM}{\@IEEEinterspaceMINratioM}%
    \bfseries
    \@@@IEEEsetfontdimens{\@IEEEinterspaceratioB}{\@IEEEinterspaceMAXratioB}{\@IEEEinterspaceMINratioB}%
  }}

% revise the interword spacing for each font shape \slshape is not often
% used for IEEE work and is not altered here. The \scshape caps are
% already a tad too large in the free LaTeX fonts (as compared to what the
% IEEE uses) so we won't alter these either.
\def\@IEEEsetfontdimens{{%
    \normalfont
    \@@IEEEsetfontdimens
    \normalfont\itshape
    \@@IEEEsetfontdimens
  }}

\def\IEEEtunefonts{{\selectfont\rmfamily
    \tiny\@IEEEsetfontdimens
    \scriptsize\@IEEEsetfontdimens
    \footnotesize\@IEEEsetfontdimens
    \small\@IEEEsetfontdimens
    \normalsize\@IEEEsetfontdimens
    \large\@IEEEsetfontdimens
    \LARGE\@IEEEsetfontdimens
    \huge\@IEEEsetfontdimens
    \Huge\@IEEEsetfontdimens}}

\makeatother
\usepackage{unicode-math}
\setmainfont{STEP}
\IEEEtunefonts
\begin{document}
hello \emph{hello}
\end{document}

Further details

I would like to find out whether this is an issue with the new font management logic or an expected behavior, to know how IEEEtran.cls will need to be patched to make it compatible with future lualatex.

[wspr]

This should now be fixed with an updated fontspec (v2.7h) — could you please check?

[callegar]

Unfortunately, not. The other way round, I now see the warnings also with regular lualatex, not just with lualatex-dev. I think that this is because the LaTeX format has now been updated to what was its pre-release at the time of submitting the bug.

[wspr]

Can you provide a document that uses a font in TeX Live? Preferably more minimal than the example above?

[wspr]

Apologies, I just re-ran in LuaLaTeX instead of XeLaTeX and I see the font is indeed available in TeX Live.

[wspr]

Here's a truly minimal example:

\documentclass{article}
\usepackage{fontspec}
\setmainfont{STEP}
{\bfseries}
\begin{document}
hello \emph{hello} \textbf{hello}
\end{document}

Sorry, I can't spend more time on this tonight...

[callegar]

Thanks for minimalizing my example. I had tried playing with \bfseries, but at the beginning I did not notice that it had to be placed before the \begin{document} to see the issue!!!

[u-fischer]

@wspr It is the already discussed problem. One way to resolve it would be if fontspec defines both b and bx:

\documentclass{article}
\usepackage{fontspec}
\setmainfont{STEP}
\DeclareFontShape{TU}{\familydefault}{bx}{n}{<-> ssub*\familydefault/b/n}{}
{\bfseries}
\begin{document}
hello \emph{hello} \textbf{hello}
\end{document}

[wspr]

@u-fischer — the working branch now has a fix for this (see above). Do you think I should push this out straight away?