fix: remove pipe_table.filler config and RenderMarkdownTableFill highlight

## Details

The table filler highlight is used for inlined spaces to pad out tables
so that columns line up nicely. However using a special highlight group
for this does not serve a purpose. There are many other instances where
we add spaces for padding and in all cases we use the default padding
highlight "Normal". To make the behavior more similar to other
components the highlight and configuration option have been removed.

In some ways this could be a breaking change, but I really can't see
a use case for having the padding stand out (i.e. using a custom
background color), I imagine all existing usage of this option set some
value that ends up having no visual effect. If any bug reports are
submitted around this I will reconsider by either adding it back or
marking this as a hard breaking change, depending on the use case.

Author: MeanderingProgrammer

README.md

@@ -730,8 +730,6 @@ require('render-markdown').setup({
         head = 'RenderMarkdownTableHead',
         -- Highlight for everything else, main table rows and the line below.
         row = 'RenderMarkdownTableRow',
-        -- Highlight for inline padding used to add back concealed space.
-        filler = 'RenderMarkdownTableFill',
         -- Determines how the table as a whole is rendered.
         -- | none   | { enabled = false }        |
         -- | normal | { border_enabled = false } |
@@ -1497,8 +1495,6 @@ require('render-markdown').setup({
         head = 'RenderMarkdownTableHead',
         -- Highlight for everything else, main table rows and the line below.
         row = 'RenderMarkdownTableRow',
-        -- Highlight for inline padding used to add back concealed space.
-        filler = 'RenderMarkdownTableFill',
         -- Determines how the table as a whole is rendered.
         -- | none   | { enabled = false }        |
         -- | normal | { border_enabled = false } |
@@ -1766,7 +1762,6 @@ The table below shows all the highlight groups with their default link
 | RenderMarkdownTodo            | @markup.raw                        | Todo custom checkbox       |
 | RenderMarkdownTableHead       | @markup.heading                    | Pipe table heading rows    |
 | RenderMarkdownTableRow        | Normal                             | Pipe table body rows       |
-| RenderMarkdownTableFill       | Conceal                            | Pipe table inline padding  |
 | RenderMarkdownSuccess         | DiagnosticOk                       | Success related callouts   |
 | RenderMarkdownInfo            | DiagnosticInfo                     | Info related callouts      |
 | RenderMarkdownHint            | DiagnosticHint                     | Hint related callouts      |

doc/render-markdown.txt

@@ -1,4 +1,4 @@
-*render-markdown.txt*        For NVIM v0.11.6       Last change: 2026 March 04
+*render-markdown.txt*        For NVIM v0.11.6       Last change: 2026 March 05
 
 ==============================================================================
 Table of Contents                          *render-markdown-table-of-contents*
@@ -796,8 +796,6 @@ Default Configuration ~
             head = 'RenderMarkdownTableHead',
             -- Highlight for everything else, main table rows and the line below.
             row = 'RenderMarkdownTableRow',
-            -- Highlight for inline padding used to add back concealed space.
-            filler = 'RenderMarkdownTableFill',
             -- Determines how the table as a whole is rendered.
             -- | none   | { enabled = false }        |
             -- | normal | { border_enabled = false } |
@@ -1547,8 +1545,6 @@ Table Configuration ~
             head = 'RenderMarkdownTableHead',
             -- Highlight for everything else, main table rows and the line below.
             row = 'RenderMarkdownTableRow',
-            -- Highlight for inline padding used to add back concealed space.
-            filler = 'RenderMarkdownTableFill',
             -- Determines how the table as a whole is rendered.
             -- | none   | { enabled = false }        |
             -- | normal | { border_enabled = false } |
@@ -1865,9 +1861,6 @@ The table below shows all the highlight groups with their default link
 
   RenderMarkdownTableRow          Normal                               Pipe table body rows
 
-  RenderMarkdownTableFill         Conceal                              Pipe table inline
-                                                                       padding
-
   RenderMarkdownSuccess           DiagnosticOk                         Success related
                                                                        callouts
 

lua/render-markdown/core/colors.lua

@@ -56,7 +56,6 @@ M.colors = {
     -- Pipe tables
     TableHead       = '@markup.heading',
     TableRow        = 'Normal',
-    TableFill       = 'Conceal',
     -- Callouts
     Success         = 'DiagnosticOk',
     Info            = 'DiagnosticInfo',

lua/render-markdown/health.lua

@@ -6,7 +6,7 @@ local state = require('render-markdown.state')
 local M = {}
 
 ---@private
-M.version = '8.11.13'
+M.version = '8.11.14'
 
 function M.check()
     M.start('versions')

lua/render-markdown/render/markdown/table.lua

@@ -288,8 +288,8 @@ function Render:row(row)
 
     if vim.tbl_contains({ 'trimmed', 'padded' }, self.config.cell) then
         for i, col in ipairs(row.cols) do
-            local node = col.node
             local delim = self.data.delim.cols[i]
+            local node = col.node
             local space = col.space
             local fill = delim.width - col.width
             -- delim(20) : --------------------
@@ -337,7 +337,7 @@ function Render:shift(node, side, amount)
     if amount > 0 then
         self.marks:add(self.config, true, node.start_row, col, {
             priority = 0,
-            virt_text = self:line():pad(amount, self.config.filler):get(),
+            virt_text = self:line():pad(amount):get(),
             virt_text_pos = 'inline',
         })
     elseif amount < 0 then

lua/render-markdown/settings.lua

@@ -1617,7 +1617,6 @@ M.pipe_table = {}
 ---@field alignment_indicator string
 ---@field head string
 ---@field row string
----@field filler string
 ---@field style render.md.table.Style
 
 ---@class (exact) render.md.table.cell.Context
@@ -1692,8 +1691,6 @@ M.pipe_table.default = {
     head = 'RenderMarkdownTableHead',
     -- Highlight for everything else, main table rows and the line below.
     row = 'RenderMarkdownTableRow',
-    -- Highlight for inline padding used to add back concealed space.
-    filler = 'RenderMarkdownTableFill',
     -- Determines how the table as a whole is rendered.
     -- | none   | { enabled = false }        |
     -- | normal | { border_enabled = false } |
@@ -1715,7 +1712,6 @@ function M.pipe_table.schema()
         alignment_indicator = { type = 'string' },
         head = { type = 'string' },
         row = { type = 'string' },
-        filler = { type = 'string' },
         style = { enum = M.pipe_table.style },
     })
 end

lua/render-markdown/types.lua

@@ -286,7 +286,6 @@
 ---@field alignment_indicator? string
 ---@field head? string
 ---@field row? string
----@field filler? string
 ---@field style? render.md.table.Style
 
 ---@class (exact) render.md.quote.UserConfig: render.md.base.UserConfig

tests/util.lua

@@ -416,7 +416,7 @@ end
 ---@param spaces integer
 ---@return vim.api.keyset.set_extmark
 function M.table.padding(spaces)
-    return M.padding(spaces, 0, 'RmTableFill')
+    return M.padding(spaces, 0)
 end
 
 ---@param marks render.md.test.Marks