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A bug (or perhaps not)

Topics/tags: Rants, technical, short

The other day, I looked at one of my musing pages and said to myself,

Hmmm … I think I’ve found a bug in Pandoc. At least I’ve found a way in which Pandoc processes Markdown differently than Markdown.pl does.

What’s the bug? An input of

[A] [Wikipedia](https://www.wikipedia.org)

should result in an output of

<p>[A] <a href="https://www.wikipedia.org">Wikipedia</a></p>

which you should see as

[A] Wikipedia.

However, Pandoc gave

<p>[A] [Wikipedia](https://www.wikipedia.org)</p>

which you see as

[A] [Wikipedia](https://www.wikipedia.org).

Am I sure about what the output should be? Pretty sure. It’s what Markdown.pl gives. It’s also what GitHub gives.

I decided to be a responsible citizen and submit a bug report. The Pandoc bug reporting guidelines suggest that one should first search the list of open issues. I started looking at all 453 open issues, or at least the titles of those issues. Then I realized that I could probably narrow the search to ones that included the word link. After some time checking whether or not the bug was already reported, and finding nothing, I decided to report the bug. The first instruction was Check your version. I did so. I realized that we have an ancient version of Pandoc installed in MathLAN. We have version 1.17.2, which I think was released in 2016. Pandoc 2.0 was released a year ago. The latest is version 2.3.1. And yes, the new version lacks the bug.

It’s time to put in a ticket [1]. In the meantime, I wonder if I can install a newer version for myself [3].

That may also explain why Pandoc didn’t always seem to match the docs.

Of course, now I’ve found that the flags I was using are no longer correct [4]. That requires some updates to my Makefile. I also need to rebuild all of the Web pages, since many of them suffered from incorrect formatting.

Next time, I’ll start by making sure that the software is up to date.


[1] Now that ITS runs MathLAN, all software requests are supposed to go through our ticketing system. Back when we had a faculty member maintaining the system, all I had to do was walk down the hall [2].

[2] Or send an encrypted email message.

[3] The answer is yes.

[4] The -S flag was removed.


Version 1.0 of 2018-10-06.