beamer duplicated fragile frame specifier

[svenevs]

The following test.md input file contents:

# Section 1

## This is Stuff {.fragile}

- Look at this list
- Is it not nice?

Yes it is.

## More Stuff {.allowframebreaks}

1. An ordered listing.
2. Is even more nice.
3. Depending on the context

Converting to beamer, see that the \begin{frame} for This is Stuff title section has [fragile,fragile]. There should be only one?

Note: functionally, this doesn't appear to be a problem. I'm actually trying to write a filter to fragile every frame instead of using sed, so I thought my filter was bad. But after running without filters I realized that it comes from pandoc.

Using pandoc version 2.5 from cabal install. pandoc -f markdown -t beamer test.md results:

\hypertarget{section-1}{%
\section{Section 1}\label{section-1}}

\begin{frame}[fragile,fragile]{This is Stuff}
\protect\hypertarget{this-is-stuff}{}

\begin{itemize}
\tightlist
\item
  Look at this list
\item
  Is it not nice?
\end{itemize}

Yes it is.

\end{frame}

\begin{frame}[allowframebreaks]{More Stuff}
\protect\hypertarget{more-stuff}{}

\begin{enumerate}
\tightlist
\item
  An ordered listing.
\item
  Is even more nice.
\item
  Depending on the context
\end{enumerate}

\end{frame}

Haskell is still quite foreign to me (a shameful imperative programmer xD), but I think it somehow gets duplicated here

pandoc/src/Text/Pandoc/Writers/LaTeX.hs

Lines 468 to 476 in 253f342

	let fragile = "fragile" `elem` classes ||
	not (null $ query hasCodeBlock elts ++ query hasCode elts)
	let frameoptions = ["allowdisplaybreaks", "allowframebreaks", "fragile",
	"b", "c", "t", "environment",
	"label", "plain", "shrink", "standout",
	"noframenumbering"]
	let optionslist = ["fragile" | fragile && isNothing (lookup "fragile" kvs)] ++
	[k | k <- classes, k `elem` frameoptions] ++
	[k ++ "=" ++ v | (k,v) <- kvs, k `elem` frameoptions]

Possibly a side-effect of #4169 ? Note there are not even any code blocks on this slide.

Hope this helps some, thanks for pandoc ❤️

[mb21]

Jep, I think your analysis is spot on. Minimal repro:

echo '# foo \n\n## bar {.fragile} \n\nbaz' | pandoc -t beamer

[mb21]

It seems that we should just remove this:

["fragile" | fragile && isNothing (lookup "fragile" kvs)] ++

and add tests to cover all combinations.

[svenevs]

Awesome, thanks for the quick turnaround!