Minted ` \begin{minted}{...}` KO but `\inputminted` OK

Question

Since a few days I can't color anymore python code with minted; I don't have any error message in the log file, only the minted output doesn't appear in the pdf file.

On the other hand, everything works strangely well with the command \inputminted. How to fix this?

MWE

\documentclass[12pt]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{minted}
\begin{document}
ABCDE
\begin{minted}{python}
def __init__(self, x, y): 
    self.x=x
    self.y=y
\end{minted}
% \inputminted ... work's 
\end{document}

Answer 1

Update (27 November 2021): This issue is now fixed in fancyvrb 4.1. In version 4.0, fancyvrb changed the handling of the lastline option so that using lastline= hides all lines (nothing is displayed). However, this also caused lastline used with no argument to hide all lines. That is, the lastline default was to hide all lines. minted uses lastline (default argument) as part of the highlighting process for minted environments, so these environments stopped displaying anything with fancyvrb 4.0. Everything works correctly again with fancyvrb 4.1, which switches lastline (default argument) back to the original behavior.

---

The relevant change seems to be \@ne -> \z@ on fancyvrb.sty line 225. This causes minted to write nothing to the temp file it uses for highlighting code, instead of writing the code.

Everything can be switched back to the original behavior, fixing minted, by adding this to the preamble:

\makeatletter
\def\FV@DefineFindStop{%
  \ifx\FancyVerbStopString\relax
    \ifnum\FancyVerbStopNum<\@ne
      \let\FV@FindStartStop\FV@@PreProcessLine
    \else
      \let\FV@FindStartStop\FV@FindStopNum
    \fi
  \else
    \let\FV@FindStartStop\FV@FindStopString
  \fi}
\makeatother

At this point (22 November 2021), I am still unsure whether this change in fancyvrb was fixing an old bug (in which case minted should adapt), introducing a new bug, or defining new behavior.

Answer 2

It is a bug/a change in the newest fancyvrb. The following prints everything with the older version but suppress the line with the newest:

\documentclass[12pt]{article}
\usepackage{fancyvrb}
\begin{document}
\begin{Verbatim}[lastline=]
blub
\end{Verbatim}

\end{document}

You should report this.

Answer 3

\documentclass[12pt]{article}
\usepackage{fancyvrb}
\makeatletter
\def\KV@FV@lastline@default{%
  \let\FancyVerbStopNum\m@ne
  \let\FancyVerbStopString\relax}
\fvset{lastline}
\makeatother
\usepackage{minted}
\begin{document}
ABCDE
\begin{minted}{python}
def __init__(self, x, y): 
    self.x=x
    self.y=y
\end{minted}
blub

\begin{Verbatim}
abc
\end{Verbatim}

\end{document}

I'll fix it and upload it to CTAN