feat: Markdown / custom processing support

[Picalines]

Hi, great plugin!

It'd be nice if this plugin could wrap TS types in a markdown symbols, like:

Type

```ts
  {
    field: number
  }
```

Is not assignable to `number`

So other plugins like noice.nvim could highlight the diagnostic popup using treesitter for example

I think there're two ways to implement it:

1. Direct option like format = 'markdown', while the current behaviour is format = 'plain' or something
2. Two generic functions for formatting blocks and inlines, line:

format = {
  inline = function (text) return '`' .. text .. '`',
  block = function (text)
    return '```ts\n' .. text .. '\n```'
  return
}

Second approach is more difficult, because we'd need to choose what data to pass in function parameters (is text already prettified? How to handle nested indentation?)

[davidosomething]

updated with:

{
    "davidosomething/format-ts-errors.nvim",
    config = function()
      require("format-ts-errors").setup({
        add_markdown = true, -- wrap output with markdown ```ts ``` markers
        start_indent_level = 0, -- initial indent
      })
    end,
}

lmk if that works

[Picalines]

It seems like the TS blocks are not indented now

Not entirely sure what's happening, i'll share a better screenshot when i found one

[davidosomething]

if you could share the file as well it would help

[Picalines]

Here's a short example:

type Obj1 = { field: number }
type Obj2 = { field: string }
const x: Obj1 = {field: 123}
const y: Obj2 = x

Current output is:

Type

```ts
Obj1
```

is not assignable to type

```ts
Obj2
```

  Types of property 'field' are incompatible.
Type

```ts
number
```

is not assignable to type

```ts
string
```

 (2322)

The (2322) is part of neovim configuration, it can be fixed on the user side

[davidosomething]

are you using start_indent_level = 0, -- initial indent ?
The default before this change was 1

[Picalines]

are you using start_indent_level = 0, -- initial indent ? The default before this change was 1

Yes, i'm using start_indent_level = 0

[davidosomething]

remove that line or change it to start_indent_level = 1 to bring back initial indent

[Picalines]

remove that line or change it to start_indent_level = 1 to bring back initial indent

It produces the same result for the example i posted above

[davidosomething]

i am unable to replicate, can you post a minimal config?
here's what i see with start_indent_level = 1

[Picalines]

Sorry, it turn's out that render-markdown plugin removes the indentation in code blocks

That's my output without the plugin:

Type

```ts
  Obj1
```

is not assignable to type

```ts
  Obj2
```

  Types of property 'field' are incompatible.
Type

```ts
  number
```

is not assignable to type

```ts
  string
```

@davidosomething
Is the Types of property 'field' are incompatible indented correctly? You can close the issue if that's intended

---

If anyone stumbles across this, you can turn off render-markdown's indent feature to keep the highlighting

Here's how i've configured neovim to render "Diagnostics" as markdown:

local builtin_open_float = vim.diagnostic.open_float

---@diagnostic disable-next-line: duplicate-set-field
vim.diagnostic.open_float = function(...)
	local bufnr, winid = builtin_open_float(...)

	if bufnr and winid then
		vim.api.nvim_set_option_value('filetype', 'markdown', { buf = bufnr })
	end

	return bufnr, winid
end

And here's how to tell neovim not to apply DiagnosticError highlight to the whole popup:

vim.diagnostic.config {
	signs = {
		-- text & numhl tables
	},

	float = {
		-- NOTE: format can't return the highlight, so we use prefix & suffix without it
		format = function() return '' end,

		prefix = function(report)
			local signs = vim.diagnostic.config().signs or {}
			local icon = signs.text[report.severity]
			return icon .. ' ', signs.numhl[report.severity]
		end,

		suffix = function(report)
			local hl = 'Normal'
			local message = vim.trim(report.user_data.lsp.message)

			if string.find(message, '\n') then
				return string.format('%s\n^ (%s)', message, report.code), hl
			end

			return string.format('%s (%s)', message, report.code), hl
		end,
	},
}

[davidosomething]

Is the Types of property 'field' are incompatible indented correctly? You can close the issue if that's intended

Yea, it comes newline+indented from typescript server.

It's possible to change the output of that as well using some regex to strip the extra indent, but the messaging changes between typescript versions so I'll leave it as an exercise to the user ;P

Thanks for using and following up on the issue!