Properly break long HTML lines when converting from Markdown to PDF

[Noki]

If you have very long words in an markdown codeblock and try to convert it to an PDF, the breaklines and breakanywhere directives do not work as expected.

Output:

Expected Output:

The long URL should be broken in between, and have an indicator showing that it's the same line. The line break should respect the page margin.

Pandoc Version:

pandoc 2.9.1.1
Compiled with pandoc-types 1.20, texmath 0.12, skylighting 0.8.3
Default user data directory: C:\Users\Tobias Schwarz\AppData\Roaming\pandoc
Copyright (C) 2006-2019 John MacFarlane
Web: https://pandoc.org
This is free software; see the source for copying conditions.
There is no warranty, not even for merchantability or fitness
for a particular purpose.

Steps to reproduce:

Use the attached pandoc.txt with the following commandline:

pandoc -f markdown -o pandoc-test.pdf pandoc-test.txt

pandoc-test.txt

Best regards
Tobias

[jgm]

This minimal case shows that the issue is that the \StringTok macro is overriding the breaking behavior. Compile with pdflatex. You'll see the first line broken (without StringTok), the second not. I don't think there's anything pandoc can do about this. It's really a limitation of fvextra. (Indeed, if you replace \StringTok with anything else, say \textbf, it also prevents breaking.)

\documentclass{article}
\usepackage{color}
\usepackage{fancyvrb}
\newcommand{\VerbBar}{|}
\newcommand{\VERB}{\Verb[commandchars=\\\{\}]}
\DefineVerbatimEnvironment{Highlighting}{Verbatim}{commandchars=\\\{\}}
% Add ',fontsize=\small' for more characters per line
\newenvironment{Shaded}{}{}
\newcommand{\StringTok}[1]{\textcolor[rgb]{0.25,0.44,0.63}{#1}}
\setlength{\emergencystretch}{3em} % prevent overfull lines
\providecommand{\tightlist}{%
  \setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}
\setcounter{secnumdepth}{-\maxdimen} % remove section numbering

\usepackage{fvextra}
\RecustomVerbatimEnvironment{Highlighting}{Verbatim}{breaklines,breakanywhere,commandchars=\\\{\}}

\author{}
\date{}

\begin{document}

\begin{Shaded}
\begin{Highlighting}[]
"https://www.example.com/dgjlb4r7cu0elacgpbdgjlb4r7cu0elacgpb/nwl4858soq59jkq5ijl5sdgjlb4r7cu0elacgpbv56uegqp500gijn7vo1s1jcsnn86an7.jpg"

\StringTok{"https://www.example.com/dgjlb4r7cu0elacgpbdgjlb4r7cu0elacgpb/nwl4858soq59jkq5ijl5sdgjlb4r7cu0elacgpbv56uegqp500gijn7vo1s1jcsnn86an7.jpg"}
\end{Highlighting}
\end{Shaded}


\end{document}

[Noki]

@jgm Thank you for pointing out that it is an fvextra issue. I opened an issue over there (gpoore/fvextra#11) and will close this issue now.