Add indent and fold files to mermaid

[aareman]

I added basic indentation and folding to mermaid files. The language only had highlights previously. (I think there is room for markdown injections by node names, but I wasn't planning to add that here)

First time contributing here, I read the Contributing.md file and still need to run the formatting scripts. Please let me know if there is anything else I need to change.

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Thank you for this amazing plugin. 🙂

[clason]

The mermaid queries are currently orphaned. Would you like to volunteer as maintainer?

[lucario387]

@indent.end seems to be missing here.

Also you need to run ./scripts/format-queries.lua queries/mermaid

[aareman]

@indent.end seems to be missing here.

I'm not sure what you mean here. Is @indent.end a required part of an indent query in neovim (I didn't see that in the docs)? By making it branch it does the following

flowchart BT
  subgraph DA
    direction BT
    a --> b
  end

flowchart BT
  subgraph DA
    direction BT
    a --> b
  end

In terms of the "end" of the first indent. There appears to be no "end" in mermaid js, since I think its one chart per file. And the TS Query Tree is rooted at document. I can't find anything contrary to this with some cursory looking. (I mostly use it in markdown -- one chart per code block)

Also you need to run ./scripts/format-queries.lua queries/mermaid

I was waiting to do this until I knew that I had a general direction to get the pr going.

[aareman]

The mermaid queries are currently orphaned. Would you like to volunteer as maintainer?

What would that entail? I would potentially be interested.

[lucario387]

What would that entail

Expected to be pinged and to have some responsiblity in fixing things when some mermaid changes happen that breaks the current queries.

[lucario387]

Also, this PR is only for flowgraph and subgraph of mermaid, is it correct? What about the other mermaid graphs, do they not exist in the queries?

[clason]

What would that entail

Expected to be pinged and to have some responsiblity in fixing things when some mermaid changes happen that breaks the current queries.

And ideally be proactive: monitor the mermaid parser and make PRs to adapt or extend the queries here before our CI fails. (Especially the latter -- if there are new nodes or such which queries need to be rewritten to make use of; our CI catches breaking changes but not possible improvements.)

As to "how": just add yourself as a maintainer in lua/nvim-treesitter/parsers.lua and remove the "experimental".

[aareman]

Also, this PR is only for flowgraph and subgraph of mermaid, is it correct? What about the other mermaid graphs, do they not exist in the queries?

That is a good point. I was thinking that there are other graphs. I can add them to the list.

I converted this PR to a draft till I make those changes

[aareman]

Added other graph types And fixed all linting/formatting issues.

I'm going to pass, for now, on the maintainer position for mermaid.

[lucario387]

Can this indent the section part in a gantt chart

gantt
    title A Gantt Diagram
    dateFormat YYYY-MM-DD
    section Section
        A task          :a1, 2014-01-01, 30d
        Another task    :after a1, 20d
    section Another
        Task in Another :2014-01-12, 12d
        another task    :24d