Problem with chemmacros, beamer and filehook-scrlfile.sty

Question

I am using chemmacros with beamer and it produces the following error

2017/08/28 basic chemmacros module (/usr/local/texlive/2019/texmf-dist/tex/latex/koma-script/scrlfile.sty Package: scrlfile 2019/10/12 v3.27 KOMA-Script package (loading files) LaTeX Warning: Command \InputIfFileExists has changed. Check if current package is valid. LaTeX Warning: Command \InputIfFileExists has changed. Check if current package is valid. ) (/usr/local/texlive/2019/texmf-dist/tex/latex/filehook/filehook-scrlfile.sty Package: filehook-scrlfile 2011/01/03 v0.1 filehook patch for scrlfile package ! Package filehook Error: Detected 'scrlfile' package with unknown definition o f \InputIfFileExists. Use the 'force' option of 'filehook' to overwrite it.. See the filehook package documentation for explanation. Type H for immediate help.

If I comment out chemmacros or use a different documentclass to beamer there is no error.

Can anyone shed any light on this?

While I do get a usable output it is disconcerting to see an error coming up in the compilation and I am not sure if it will cause a fatal output in different usage of chemmacros . Is this a bug in KOMA-script as I believe it was recently updated but chemmacros wasn't.

\documentclass{beamer}
\usepackage{chemmacros}
\begin{document}

Test

\end{document}

Answer 1

The problem has been resolved by an update of the sansmathaccent package. It now no longer uses the filehook package.

Answer 2

The issue has been fixed in the last filehook update. An update to your LaTeX installation should resolve the issue. (Additionally, as Ulrike wrote, sansmathaccent had already been changed not to use filehook, which removed this particular incompatibility.)

---

As noted in the comments, the problem is that filehook-scrlfile has not been updated to work with the new definition of \InputIfFileExists in scrlfile. Until the author updates this file accordingly, as a workaround, you can place a file called filehook-scrlfile.sty with the following content in your compilation directory.

%% Modified version of filehook-scrlfile as a workaround.
%% See https://tex.stackexchange.com/a/515183/48973.
%%
\NeedsTeXFormat{LaTeX2e}[1999/12/01]
\ProvidesPackage{filehook-scrlfile}[2011/01/03 v0.1 filehook patch for scrlfile package]
\RequirePackage{filehook}
\begingroup
\long\def\scrlfile@InputIfFileExists#1#2{%
  \begingroup\expandafter\expandafter\expandafter\endgroup
  \expandafter\ifx\csname #1-@alias\endcsname\relax
    \expandafter\@secondoftwo
  \else
    \scr@replacefile@msg{\csname #1-@alias\endcsname}{#1}%
    \expandafter\@firstoftwo
  \fi
  {%
    \expandafter\InputIfFileExists\expandafter{\csname
      #1-@alias\endcsname}{#2}%
  }%
  {\IfFileExists{#1}{%
      \expandafter\scr@input@withhook\expandafter{\@filef@und}{#1}{#2}%
    }}%
}
\long\def\filehook@scrlfile@InputIfFileExists#1#2{%
  \begingroup\expandafter\expandafter\expandafter\endgroup
  \expandafter\ifx\csname #1-@alias\endcsname\relax
    \expandafter\@secondoftwo
  \else
    \scr@replacefile@msg{\csname #1-@alias\endcsname}{#1}%
    \expandafter\@firstoftwo
  \fi
  {%
    \expandafter\InputIfFileExists\expandafter{\csname
      #1-@alias\endcsname}{#2}%
  }%
  {\IfFileExists{#1}{%
      \expandafter\filehook@swap
      \expandafter{\@filef@und}%
      {\scr@load@hook{before}{#1}%
      #2\@addtofilelist{#1}%
      \filehook@every@atbegin{#1}%
      \filehook@atbegin{#1}%
      \@@input}%
      \filehook@atend{#1}%
      \filehook@every@atend{#1}%
      \scr@load@hook{after}{#1}%
    }}%
}
\long\def\filehook@@scrlfile@InputIfFileExists#1#2{%
  \let\InputIfFileExists\filehook@InputIfFileExists
  \begingroup\expandafter\expandafter\expandafter\endgroup
  \expandafter\ifx\csname #1-@alias\endcsname\relax
    \expandafter\@secondoftwo
  \else
    \scr@replacefile@msg{\csname #1-@alias\endcsname}{#1}%
    \expandafter\@firstoftwo
  \fi
  {%
    \expandafter\InputIfFileExists\expandafter{\csname
      #1-@alias\endcsname}{#2}%
  }%
  {\IfFileExists{#1}{%
      \expandafter\filehook@swap
      \expandafter{\@filef@und}%
      {\scr@load@hook{before}{#1}%
      #2\@addtofilelist{#1}%
      \filehook@atbegin{#1}%
      \@@input}%
      \filehook@atend{#1}%
      \scr@load@hook{after}{#1}%
    }}%
}
\ifcase
    \expandafter\ifx\csname InputIfFileExists \endcsname\latex@InputIfFileExists 0\else
    \expandafter\ifx\csname InputIfFileExists \endcsname\scrlfile@InputIfFileExists 0\else
     1%
    \fi\fi
\relax
  \global\let\filehook@InputIfFileExists\filehook@scrlfile@InputIfFileExists
  \global\let\filehook@@InputIfFileExists\filehook@@scrlfile@InputIfFileExists
  \global\expandafter\let\csname InputIfFileExists \endcsname\filehook@InputIfFileExists
  \PackageInfo{filehook}{Package 'scrlfile' detected and compensated for}%
\else
  \iffilehook@force
    \global\let\filehook@InputIfFileExists\filehook@default@InputIfFileExists
    \global\let\filehook@@InputIfFileExists\filehook@@default@InputIfFileExists
    \global\expandafter\let\csname InputIfFileExists \endcsname\filehook@InputIfFileExists
    \PackageWarning{filehook}{Detected 'scrlfile' package with unknown definition of \string\InputIfFileExists.^^J%
                              The 'force' option of 'filehook' is in effect. Macro is overwritten with default!}%
  \else
    \show\InputIfFileExists
    \expandafter\show\csname InputIfFileExists \endcsname
    \show\scrlfile@InputIfFileExists
    \PackageError{filehook}{Detected 'scrlfile' package with unknown definition of \string\InputIfFileExists.^^J%
                            Use the 'force' option of 'filehook' to overwrite it.}{}%
  \fi
\fi
\endgroup
\endinput
%%
%% End of file `filehook-scrlfile.sty'.

Answer 3

I am on a Windows 10 system using TeXstudio. I updated MiKTeX 2.9 on 1/9/2020 and still have the filehook error. By using the \PassOptionsToPackage{force}{filehook} command in my preamble, my \include commands are working again. I hope this may help someone.