--syntax-definition doesn't work with absolute paths in Windows

[THS-on]

System info

• Pandoc 2.9.2.1
• Tested using Windows 10 and 7
• Tested using cmd.exe and calling pandoc using python subprocess

If I use the absolute path for --syntax-definition it will fail with the following message.

C:\Users\User\Desktop>pandoc --syntax-definition C:\Users\User\Desktop\cpp.xml test.md
pandoc: file:///C:/Users/User/Desktop/cpp.xml: openBinaryFile: invalid argument (Invalid argument)

Relative paths work fine.

C:\Users\User\Desktop>pandoc --syntax-definition cpp.xml test.md


C:\Users\User\Desktop>

To recreate this problem

• Download https://github.com/jgm/skylighting/blob/master/skylighting-core/xml/cpp.xml
• Create empty test.md
• run pandoc --syntax-definition C:\path\to\cpp.xml test.md

[jgm]

See #4836, which I thought could be fixed by turning this into a file: URL -- but the OP never confirmed that the fix worked, and I wasn't able to test it myself since I don't have a windows box to test on.

[THS-on]

Thanks for the quick reply. I switched my scripts to use relative paths under Windows, to make them work.
If I find the time I'll setup Haskell on Windows and try to debug it. At which parts of pandoc and hxt should I look?
Can this be fixed in pandoc or should I look into fixing it in hxt?

[jgm]

Fixing in HXT would be best, if the maintainer is responsive (I never got any reply to my bug report). I'm not sure how to fix in pandoc, but maybe there's something I haven't thought of.

[tim-elmer]

See #4836, which I thought could be fixed by turning this into a file: URL -- but the OP never confirmed that the fix worked, and I wasn't able to test it myself since I don't have a windows box to test on.

Tested with Pandoc 2.14.2, file protocol is prepended by pandoc, but error is still thrown: pandoc.exe: file:///C:/Users/XYZ: openBinaryFile: invalid argument (Invalid argument).

jgm/skylighting@16e3001 doesn't seem to have resolved the issue.

[jgm]

Since all of this, we've switched from HXT to xml-conduit in skylighting.
So the commit you mention isn't even in the code any more; file:// is being prepended by pandoc's command line option parser, but it shouldn't be any more. (I'll change this; maybe it will help, maybe not.)

[jgm]

Done in 5a1bd52
Please test (nightly should be available by tomorrow).

[tim-elmer]

This may be me being obtuse, but I'm assuming you're referring to master branch. Tried cloning and building it but I'm not having any luck (stack install log: https://pastebin.com/WFisqkgQ). I don't know how much effort you want to put into walking me through getting a test build working.

Relative paths work for me.

[jgm]

Try a (precompiled) nightly, you don't need to build it yourself.
https://github.com/jgm/pandoc/actions/runs/1319449072

[tim-elmer]

Ah, missed that, thanks. That build does appear to resolve the issue. I was able to process a markdown document to html with an absolutely pathed syntax definition.

👍

[THS-on]

I can confirm that this fixes the issue.