Add Luau file type support

[NeonD00m]

Feature Description

Github supports Luau. github-linguist/linguist#6000

Screenshots

No response

[wxiaoguang]

• Luau "linguist" is detected by github.com/go-enry/go-enry/v2, it seems that it already supports "luau"

  • go-enry luau

    

• Highlighting is powered by github.com/alecthomas/chroma/v2 , you could also use this approach: update the [highlight.mapping] section in your "app.ini", use Lua hightlighting

  • .omnijs - .json #33360 (comment)

[silverwind]

Is syntax the same as lua? If yes, just PR the file extension into chroma and it will automatically work in gitea:

https://github.com/alecthomas/chroma/blob/4b0882a15f49a23c272b79b5af541bf918b98998/lexers/embedded/lua.xml#L5-L6

Edit: According to this Linguist treats it as an alias to lua, so above is a good start:

https://github.com/github-linguist/linguist/pull/6612/files#diff-9c337ec09ccaaa1374713aad9ba26cdc1308586a27cb309a883a0b19bde663d8R3937-R3938

[silverwind]

alecthomas/chroma#1056

[NeonD00m]

It's not the same syntax as Lua. It's backwards compatible but there are substantial additions in syntax. See here: https://luau.org/

[wxiaoguang]

For "highlighting", the syntax is more than 90% the same I guess, so I think at the moment it should be good enough to use "lua" syntax to highlight "luau" files.

[silverwind]

It's not the same syntax as Lua. It's backwards compatible but there are substantial additions in syntax. See here: https://luau.org/

Right, but highlighting as lua is better than no highlighting imho. Also GitHub seems to highlight it as lua, at least in their CodeMirror, not sure about Prettylights but likely the same.

Also, monaco-editor does not support lual, and I can't even find an issue on https://github.com/microsoft/monaco-editor about it.