Line feed following printable character is detected as an error for VimL

[mmrwoods]

I'm using glow to preview markdown within Vim and have noticed that for code blocks with the language set to vim, a line feed following a printable character is always shown as an error, e.g.

The first code block here has the language set to vim, the other set to ruby, line feed following a printable character is always shown as an error for vim code blocks.

Glow depends on glamour to render markdown, and Glamour depends on Chroma to add syntax highlighting to code blocks.

It looks like the root cause of this issue is that Chroma is detecting a line feed following a printable character as an error, e.g.

$ echo "set foo" > foo.vim
$ chroma -f json foo.vim
[
  {"type":"NameOther","value":"set"},
  {"type":"Text","value":" "},
  {"type":"NameOther","value":"foo"},
  {"type":"Error","value":"\n"}
]

Glamour then highlights this as an error with a red background when rendering the code block, and that's what I end up seeing in the output from Glow. I can work around this telling glow to use custom styles and just override the rendering of errors in code blocks, but that's quite a nasty hack, so it would be really nice to see this fixed in Chroma (assuming Chroma is really the root cause here, and I may well have assumed incorrectly that Chroma is at fault).

I will try to find some time to fix this myself and open a PR, but I'm not familiar with this code at all, so It thought I'd open an issue first as this might be a simple fix for someone who knows the code.

[alecthomas]

I would suggest trying to replicate this in the Chroma playground, which will eliminate the many layers of indirection at play.

[mmrwoods]

You can re-produce it in the playground, you will see the error span in the html output.

[alecthomas]

Ah sorry, I somehow missed your invocation from the command line 🤦

Thanks for doing that.

[alecthomas]

Should be fixed. I also added a couple more keywords to vim, though there are millions of them so...

[mmrwoods]

Fantastic, thank you very much 👍