chore: add counter to decorator

## Details

Adds `n` field to buffer level decorator, at times is useful to know how
many changes have been processed for the buffer. Currently unused, may
get added to debug logs.

Handle `Context.new` returning `nil`, currently not possible, will be
once we transition to async parsing. For now simply leads to another
path that runs `callback(nil)`.

Author: MeanderingProgrammer

CHANGELOG.md

@@ -2,6 +2,11 @@
 
 ## Pre-release
 
+### Features
+
+- configurable indent extmark priority [1327150](https://github.com/MeanderingProgrammer/render-markdown.nvim/commit/1327150da9b272863355f28e523050ab5450412f)
+- more anti_conceal.ignore elements [b8c3d47](https://github.com/MeanderingProgrammer/render-markdown.nvim/commit/b8c3d474d4da14fa1a5f9a0a18955c6e7db88f65)
+
 ## 8.6.0 (2025-07-09)
 
 ### Features

doc/render-markdown.txt

@@ -1,4 +1,4 @@
-*render-markdown.txt*        For NVIM v0.11.2        Last change: 2025 July 14
+*render-markdown.txt*        For NVIM v0.11.2        Last change: 2025 July 15
 
 ==============================================================================
 Table of Contents                          *render-markdown-table-of-contents*

lua/render-markdown/core/ui.lua

@@ -165,10 +165,14 @@ function Updater:parse(callback)
     if ok and parser then
         -- reset buffer context
         local context = Context.new(self.buf, self.win, self.config, self.mode)
-        -- make sure injections are processed
-        context.view:parse(parser)
-        local marks = handlers.run(context, parser)
-        callback(iter.list.map(marks, Extmark.new))
+        if context then
+            -- make sure injections are processed
+            context.view:parse(parser)
+            local marks = handlers.run(context, parser)
+            callback(iter.list.map(marks, Extmark.new))
+        else
+            callback(nil)
+        end
     else
         log.buf('error', 'Fail', self.buf, 'no treesitter parser found')
         callback(nil)

lua/render-markdown/health.lua

@@ -5,7 +5,7 @@ local state = require('render-markdown.state')
 local M = {}
 
 ---@private
-M.version = '8.6.2'
+M.version = '8.6.3'
 
 function M.check()
     M.start('version')

lua/render-markdown/lib/decorator.lua

@@ -6,6 +6,7 @@ local compat = require('render-markdown.lib.compat')
 ---@field private running boolean
 ---@field private marks render.md.Extmark[]
 ---@field private tick integer?
+---@field n integer
 local Decorator = {}
 Decorator.__index = Decorator
 
@@ -18,6 +19,7 @@ function Decorator.new(buf)
     self.running = false
     self.marks = {}
     self.tick = nil
+    self.n = 0
     return self
 end
 
@@ -40,6 +42,7 @@ end
 function Decorator:set(marks)
     self.marks = marks
     self.tick = self:get_tick()
+    self.n = self.n + 1
 end
 
 ---@param debounce boolean

lua/render-markdown/request/context.lua

@@ -85,7 +85,7 @@ end
 ---@param win integer
 ---@param config render.md.buf.Config
 ---@param mode string
----@return render.md.request.Context
+---@return render.md.request.Context?
 function M.new(buf, win, config, mode)
     local view = View.new(buf)
     local context = Context.new(buf, win, config, mode, view)