robust-externalize fails to handle code that cares about newlines (such as inline tables well in tikz)

[JasonGross]

Parallel to sasozivanovic/memoize#19
This code only works if I comment out \cacheTikz

\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usepackage{robust-externalize}
\cacheTikz
\robExtConfigure{
  add to preset={tikz}{
    add to preamble={
      \usepackage{pgfplots}
      \pgfplotsset{compat=newest}
    }
  },
}
\begin{document}
\begin{tikzpicture}
\begin{axis}
\addplot [semithick, black]
table {%
0 0
0.0752933174371719 0.0355731099843979
};
\end{axis}
\end{tikzpicture}
\end{document}

Otherwise it errors with

(/usr/local/texlive/2024/texmf-dist/tex/generic/pgfplots/pgfplots.markers.code.

(robExt)                tex)
(robExt)                ! Package pgfplots Error: Could not read table file
(robExt)                '"0 0 0.0752933174371719 0.
(robExt)                0355731099843979 "' in 'search path=.'. In case you
(robExt)                intended to provide inline
(robExt)                data: maybe TeX screwed up your end-of-lines? Try
(robExt)                `row sep=crcr' and terminate
(robExt)                your lines with `\\' (refer to the pgfplotstable
(robExt)                manual for details).
(robExt)                !  ==> Fatal error occurred, no output PDF file
(robExt)                produced!
(robExt)                Transcript written on
(robExt)                robExt-346C97BA17A0E18DFE55ADF736F7902C.log.
(robExt)
(robExt)                ^^^^^^
(robExt)                See full logs below (you might need to press ENTER
(robExt)                to go to the next error) or in
(robExt)
robustExternalize/robExt-346C97BA17A0E18DFE55ADF736F7902C-compilation.log.

Type <return> to continue.
 ...

l.23 \end
         {tikzpicture}
?

[tobiasBora]

The problem here is that pgf expects the lines to be preserved. The problem is that LaTeX gives us 2 options to parse the inputs:

• in "macro" mode (default in robust-externalize): can be used anywhere, but the format is not precisely preserved (new lines are removed for instance, lines starting with % are removed…)
• in "verbatim" mode: the formating is preserved, but this cannot be used inside most macros

The solution here is to use CacheMeCode instead of CacheMe (used internally by tikz), which uses the verbatim mode. This can be done by replacing

\begin{tikzpicture}
…
\end{tikzpicture}

with

\begin{CacheMeCode}{tikzpicture}
\end{CacheMeCode}

like in:

\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usepackage{robust-externalize}
\cacheTikz
\robExtConfigure{
  add to preset={tikz}{
    add to preamble={
      \usepackage{pgfplots}
      \pgfplotsset{compat=newest}
    }
  },
}

\begin{document}
\begin{CacheMeCode}{tikzpicture}
\begin{axis}
\addplot [semithick, black]
table {%
0 0
0.0752933174371719 0.0355731099843979
};
\end{axis}  
\end{CacheMeCode}
\end{document}

You can also choose a different name like:

\NewDocumentEnvironment{tikzpictureVerb}{}{\CacheMeCode{tikzpicture}}{\endCacheMeCode}

or replace the existing tikzpicture environment with the verbatim version (warning: not sure if it can have some side effects):

\RenewDocumentEnvironment{tikzpicture}{}{\CacheMeCode{tikzpicture}}{\endCacheMeCode}

MWE:

\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usepackage{robust-externalize}
\cacheTikz
\robExtConfigure{
  add to preset={tikz}{
    add to preamble={
      \usepackage{pgfplots}
      \pgfplotsset{compat=newest}
    }
  },
}

%% Create a new env
\NewDocumentEnvironment{tikzpictureVerb}{}{\CacheMeCode{tikzpicture}}{\endCacheMeCode}
%% Replace existing env
\RenewDocumentEnvironment{tikzpicture}{}{\CacheMeCode{tikzpicture}}{\endCacheMeCode}

\begin{document}
\begin{tikzpicture}
\begin{axis}
\addplot [semithick, black]
table {%
0 0
0.0752933174371719 0.0355731099843979
};
\end{axis}
\end{tikzpicture}
\end{document}

If you find this solution good enough for your need, we can close this.

[tobiasBora]

In any case, I'll let this issue open until I document this behavior, and I'd like to try to fix https://tex.stackexchange.com/questions/718003/alias-of-verbatim-environment-with-optional-arguments