ltkeys: Global options starting surrounded by spaces in the input are not removed from the unused option list

[Skillmon]

Brief outline of the bug

The current code used to remove keys from the unused options list doesn't first strip spaces from the key name, which results in false-positives in the unused options list.

Minimal example showing the bug

\RequirePackage{latexbug}       % <--should be always the first line (see CONTRIBUTING)!

\begin{filecontents}{bugreport.sty}
\DeclareKeys{foo.store=\myfoo, bar.store=\mybar, baz.store=\mybaz}
\ProcessKeyOptions
\ProvidesPackage{bugreport}
\end{filecontents}

\documentclass[foo =bar, bar=baz, baz = foo]{article}

  % Any preamble code goes here
\usepackage{bugreport}

\typeout{%
  foo: \myfoo^^J%
  bar: \mybar^^J%
  baz: \mybaz^^J%
}

\begin{document}
\end{document}

Log file (required) and possibly PDF file

bugreport.log

[Skillmon]

First found thanks to https://tex.stackexchange.com/questions/706935/why-do-i-get-unused-global-options-warning-for-options-forwarded-to-a-package

[josephwright]

Fixed in dev?

[Skillmon]

It is fixed in main see #1239. The ltnews39 entry is still missing. Also, currently the fix wasn't merged into develop, so the -dev formats still throw the warning, while the normal formats don't.

[tweh]

As far as I understood this issue is fixed however I came across this while implementing an expl3 class and the following MWE still show this issue (with TeXLive 2024, up-to-date on macOS, up-to-date)

\RequirePackage{latexbug}       % <--should be always the first line (see CONTRIBUTING)!

\begin{filecontents}{democlass.cls}
\ProvidesExplClass {democlass} {2024/07/22} {1} {demo}
\LoadClassWithOptions { scrbook }
\tl_new:N \l_demo_word_tl
\keys_define:nn { democlass } {
  word .tl_set:N = \l_demo_word_tl,
}
\ProcessKeyOptions [ democlass ]
\newcommand{\myword}{\tl_use:N \l_demo_word_tl}
\end{filecontents}

\documentclass[word =xx]{democlass}

% Any preamble code goes here
\usepackage{bugreport}

\begin{document}
Test: \myword
\end{document}

Am I doing something wrong or is this bug still persistent?

[muzimuzhi]

@tweh It seems the problem only reproduces with Koma-Script document classes like scrbook or scrartcl, but not with standard ones like article.

\documentclass[foo =xx]{scrbook}
\makeatletter
% article.cls, unused options: <foo>
% scrbook.cls, unused options: <foo >, note the trailing space
\PackageError{debug}{unused options: <\@unusedoptionlist>}{}
\makeatother

\begin{document}
content
\end{document}

[muzimuzhi]

Looks like \OptionNotUsed is the culprit. Here's a reproducing example with article:

\RequirePackage{latexbug}       % <--should be always the first line (see CONTRIBUTING)!
\begin{filecontents}[force]{democlass.cls}
\LoadClass{article}
\DeclareKeys {word .code = \OptionNotUsed}
\ProcessKeyOptions
\end{filecontents}

\documentclass[word =xx]{democlass}

\begin{document}
\end{document}

In log

LaTeX Warning: Unused global option(s):
    [word ].

\OptionNotUsed only removes =<value> from \CurrentOption whose value may have form <key>=<value>, but doesn't trim spaces from <key>.

latex2e/base/ltclass.dtx

Lines 1522 to 1527 in 22375e7

	\def\OptionNotUsed{%
	\ifx\@currext\@clsextension
	\xdef\@unusedoptionlist{%
	\ifx\@unusedoptionlist\@empty\else\@unusedoptionlist,\fi
	\expandafter\@remove@eq@value\CurrentOption=\@nil}%
	\fi}

[muzimuzhi]

One way is to add space-trimming to \@remove@eq@value, which is only used in two fully-expansion places.

\ExplSyntaxOn
% \def\@remove@eq@value#1=#2\@nil{#1} % before
\def\@remove@eq@value#1=#2\@nil{\tl_trim_spaces:n{#1}}
\ExplSyntaxOff

latex2e/base/ltclass.dtx

Lines 1524 to 1526 in 22375e7

	\xdef\@unusedoptionlist{%
	\ifx\@unusedoptionlist\@empty\else\@unusedoptionlist,\fi
	\expandafter\@remove@eq@value\CurrentOption=\@nil}%

latex2e/base/ltclass.dtx

Lines 1744 to 1745 in 22375e7

	\@expandtwoargs\@removeelement
	{\expandafter\@remove@eq@value\CurrentOption=\@nil}%

[josephwright]

@muzimuzhi Make a PR?