feat: support on attach callback to integrate external latex support

## Details

Adds `on.attach` configurable function callback. This can be used to
trigger events or other functionality that helps render a markdown
document.

The concrete use case has to do with triggering an external latex
renderer since it does not generate any autocommands and requires the
user to call it via function, keymap, or otherwise.

While there is currently only a single callback point on attach this can
potentially be expanded in the future to trigger other callbacks at
other points in the rendering lifecycle. I do not have any concrete use
cases for this now so will leave this up to feature requests.

Author: MeanderingProgrammer

CHANGELOG.md

@@ -2,6 +2,16 @@
 
 ## Pre-release
 
+### Features
+
+- margin for paragraphs [#200](https://github.com/MeanderingProgrammer/render-markdown.nvim/issues/200)
+  [d20d19f](https://github.com/MeanderingProgrammer/render-markdown.nvim/commit/d20d19fa54965f6eb94558c0b84fe9a942169fb4)
+
+### Bug Fixes
+
+- bullet point right padding priority [#199](https://github.com/MeanderingProgrammer/render-markdown.nvim/issues/199)
+  [b02c8ef](https://github.com/MeanderingProgrammer/render-markdown.nvim/commit/b02c8ef72b10537a346556696b6e7fb354c8771f)
+
 ## 7.3.0 (2024-10-04)
 
 ### Features

README.md

@@ -190,6 +190,10 @@ require('render-markdown').setup({
         -- Amount of empty lines below LaTeX blocks
         bottom_pad = 0,
     },
+    on = {
+        -- Called when plugin initially attaches to a buffer
+        attach = function() end,
+    },
     heading = {
         -- Turn on / off heading icon & background rendering
         enabled = true,

doc/limitations.md

@@ -7,45 +7,49 @@
 `LaTeX` formula evaluations are placed above text rather than overlayed.
 
 A way around this is to use a separate plugin for `LaTeX` and disable that feature
-in this plugin. As examples you can use:
+in this plugin. Different plugins will have different setups, below are some examples:
 
 [latex.nvim](https://github.com/ryleelyman/latex.nvim)
 
 ```lua
 {
-    'ryleelyman/latex.nvim',
-    config = function()
-        require('latex').setup({})
-    end,
+    { 'ryleelyman/latex.nvim', opts = {} },
+    {
+        'MeanderingProgrammer/render-markdown.nvim',
+        dependencies = { 'nvim-treesitter/nvim-treesitter', 'echasnovski/mini.nvim' },
+        opts = {
+            latex = { enabled = false },
+            win_options = { conceallevel = { rendered = 2 } },
+        },
+    },
 }
 ```
 
 [nabla.nvim](https://github.com/jbyuki/nabla.nvim)
 
 ```lua
 {
-    'jbyuki/nabla.nvim',
-    config = function()
-        require('nabla').enable_virt({ autogen = true })
-    end,
-}
-```
-
-In both cases you'll need to disable `LaTeX` for this plugin:
-
-```lua
-require('render-markdown').setup({
-    latex = { enabled = false },
-    win_options = {
-        conceallevel = { rendered = 2 },
+    { 'jbyuki/nabla.nvim' },
+    {
+        'MeanderingProgrammer/render-markdown.nvim',
+        dependencies = { 'nvim-treesitter/nvim-treesitter', 'echasnovski/mini.nvim' },
+        opts = {
+            latex = { enabled = false },
+            win_options = { conceallevel = { rendered = 2 } },
+            on = {
+                attach = function()
+                    require('nabla').enable_virt({ autogen = true })
+                end,
+            },
+        },
     },
-})
+}
 ```
 
 > [!NOTE]
 >
 > These plugins can rely on a specific `conceallevel` to work properly, which
-> you will need to configure in this plugin like in the example above.
+> you will need to configure in this plugin like in the examples above.
 
 ## Does Not Run in Telescope Preview
 

doc/render-markdown.txt

@@ -239,6 +239,10 @@ Default Configuration ~
             -- Amount of empty lines below LaTeX blocks
             bottom_pad = 0,
         },
+        on = {
+            -- Called when plugin initially attaches to a buffer
+            attach = function() end,
+        },
         heading = {
             -- Turn on / off heading icon & background rendering
             enabled = true,

lua/render-markdown/debug/validator.lua

@@ -1,49 +1,51 @@
 ---@class render.md.debug.ValidatorSpec
 ---@field private validator render.md.debug.Validator
----@field private nilable? boolean
----@field private suffix string
----@field private input? table<string, any>
+---@field private config? table<string, any>
+---@field private nilable boolean
+---@field private path string
 ---@field private opts table<string, vim.validate.Spec>
 local Spec = {}
 Spec.__index = Spec
 
 ---@param validator render.md.debug.Validator
----@param path string
----@param input table<string, any>
+---@param config table<string, any>
+---@param nilable boolean
 ---@param key? string|string[]
----@param nilable? boolean
+---@param path? string
 ---@return render.md.debug.ValidatorSpec
-function Spec.new(validator, path, input, key, nilable)
+function Spec.new(validator, config, nilable, key, path)
     local self = setmetatable({}, Spec)
     self.validator = validator
+    self.config = config
     self.nilable = nilable
-    self.suffix = path
-    self.input = input
+    self.path = path or ''
     self.opts = {}
     if key ~= nil then
         key = type(key) == 'table' and key or { key }
-        self.suffix = self.suffix .. '.' .. table.concat(key, '.')
-        self.input = vim.tbl_get(self.input, unpack(key))
-        assert(self.input ~= nil or self.nilable == true)
+        self.path = self.path .. '.' .. table.concat(key, '.')
+        self.config = vim.tbl_get(self.config, unpack(key))
+        assert(self.config ~= nil or self.nilable)
     end
     return self
 end
 
 ---@return string
-function Spec:get_suffix()
-    return self.suffix
+function Spec:get_path()
+    return self.path
 end
 
 ---@return table<string, any>
-function Spec:get_input()
-    return self.input
+function Spec:get_config()
+    return self.config
 end
 
+---@param nilable boolean
 ---@param f fun(spec: render.md.debug.ValidatorSpec)
----@param nilable? boolean
-function Spec:for_each(f, nilable)
-    for name in pairs(self.input or {}) do
-        f(Spec.new(self.validator, self.suffix, self.input, name, nilable))
+function Spec:for_each(nilable, f)
+    for name in pairs(self.config or {}) do
+        local spec = Spec.new(self.validator, self.config, nilable, name, self.path)
+        f(spec)
+        spec:check()
     end
 end
 
@@ -123,7 +125,7 @@ function Spec:handle_types(input_types)
     else
         types = input_types
     end
-    if self.nilable then
+    if self.nilable and not vim.tbl_contains(types, 'nil') then
         table.insert(types, 'nil')
     end
     return types, #types == 0 and '' or (' or type ' .. vim.inspect(types))
@@ -135,20 +137,24 @@ end
 ---@param message string?
 ---@return render.md.debug.ValidatorSpec
 function Spec:add(keys, logic, message)
-    if self.input ~= nil then
+    if self.config ~= nil then
         keys = type(keys) == 'table' and keys or { keys }
         for _, key in ipairs(keys) do
             ---@diagnostic disable-next-line: assign-type-mismatch
-            self.opts[key] = { self.input[key], logic, message or self.nilable }
+            self.opts[key] = { self.config[key], logic, message or self.nilable }
         end
     end
     return self
 end
 
 function Spec:check()
-    if self.input ~= nil then
-        self.validator:check(self.suffix, self.input, self.opts)
+    if self.config == nil then
+        return
     end
+    if vim.tbl_count(self.opts) == 0 then
+        return
+    end
+    self.validator:check(self.path, self.config, self.opts)
 end
 
 ---@class render.md.debug.Validator
@@ -165,25 +171,25 @@ function Validator.new()
     return self
 end
 
----@param path string
----@param input table<string, any>
+---@param config table<string, any>
+---@param nilable boolean
 ---@param key? string|string[]
----@param nilable? boolean
+---@param path? string
 ---@return render.md.debug.ValidatorSpec
-function Validator:spec(path, input, key, nilable)
-    return Spec.new(self, path, input, key, nilable)
+function Validator:spec(config, nilable, key, path)
+    return Spec.new(self, config, nilable, key, path)
 end
 
 ---@param suffix string
----@param input table<string, any>
+---@param config table<string, any>
 ---@param opts table<string, vim.validate.Spec>
-function Validator:check(suffix, input, opts)
+function Validator:check(suffix, config, opts)
     local path = self.prefix .. suffix
     local ok, err = pcall(vim.validate, opts)
     if not ok then
         table.insert(self.errors, path .. '.' .. err)
     end
-    for key, _ in pairs(input) do
+    for key, _ in pairs(config) do
         if opts[key] == nil then
             table.insert(self.errors, string.format('%s.%s: is not a valid key', path, key))
         end

lua/render-markdown/health.lua

@@ -4,7 +4,7 @@ local state = require('render-markdown.state')
 local M = {}
 
 ---@private
-M.version = '7.3.2'
+M.version = '7.3.3'
 
 function M.check()
     M.start('version')

lua/render-markdown/init.lua

@@ -11,6 +11,9 @@ local M = {}
 ---@field public extends? boolean
 ---@field public parse fun(root: TSNode, buf: integer): render.md.Mark[]
 
+---@class (exact) render.md.UserCallback
+---@field public attach? fun(buf: integer)
+
 ---@class (exact) render.md.UserLatex
 ---@field public enabled? boolean
 ---@field public converter? string
@@ -204,6 +207,7 @@ local M = {}
 ---@field public file_types? string[]
 ---@field public injections? table<string, render.md.UserInjection>
 ---@field public latex? render.md.UserLatex
+---@field public on? render.md.UserCallback
 ---@field public overrides? render.md.UserConfigOverrides
 ---@field public custom_handlers? table<string, render.md.Handler>
 
@@ -272,6 +276,10 @@ M.default_config = {
         -- Amount of empty lines below LaTeX blocks
         bottom_pad = 0,
     },
+    on = {
+        -- Called when plugin initially attaches to a buffer
+        attach = function() end,
+    },
     heading = {
         -- Turn on / off heading icon & background rendering
         enabled = true,

lua/render-markdown/manager.lua

@@ -51,7 +51,10 @@ function M.attach(buf)
     if not M.should_attach(buf) then
         return
     end
+
     local config = state.get(buf)
+    state.on.attach(buf)
+
     local events = { 'BufWinEnter', 'BufLeave', 'CursorHold', 'CursorMoved', 'WinScrolled' }
     local change_events = { 'DiffUpdated', 'ModeChanged', 'TextChanged' }
     if config:render('i') then