feat: add enabled flag to link footnote

## Details

Based on: #362

Changes behavior of how footnotes are rendered.

Previously setting `superscript = false` would completely disable the
rendering of footnotes. Now this simply disables the conversion to
superscripts. The `^` will continue to be hidden and `prefix` and
`suffix` will be added to the contents.

Disabling rendering for footnotes entirely is now controlled by the new
`enabled` option under the `footnote` configuration.

Co-Authored-By: Varun Narravula <varun@snare.dev>

Author: MeanderingProgrammer

README.md

@@ -638,11 +638,13 @@ require('render-markdown').setup({
         render_modes = false,
         -- How to handle footnote links, start with a '^'.
         footnote = {
+            -- Turn on / off footnote rendering.
+            enabled = true,
             -- Replace value with superscript equivalent.
             superscript = true,
-            -- Added before link content when converting to superscript.
+            -- Added before link content.
             prefix = '',
-            -- Added after link content when converting to superscript.
+            -- Added after link content.
             suffix = '',
         },
         -- Inlined with 'image' elements.
@@ -1288,11 +1290,13 @@ require('render-markdown').setup({
         render_modes = false,
         -- How to handle footnote links, start with a '^'.
         footnote = {
+            -- Turn on / off footnote rendering.
+            enabled = true,
             -- Replace value with superscript equivalent.
             superscript = true,
-            -- Added before link content when converting to superscript.
+            -- Added before link content.
             prefix = '',
-            -- Added after link content when converting to superscript.
+            -- Added after link content.
             suffix = '',
         },
         -- Inlined with 'image' elements.

doc/render-markdown.txt

@@ -1,4 +1,4 @@
-*render-markdown.txt*           For 0.10.0          Last change: 2025 March 14
+*render-markdown.txt*           For 0.10.0          Last change: 2025 March 16
 
 ==============================================================================
 Table of Contents                          *render-markdown-table-of-contents*
@@ -703,11 +703,13 @@ Default Configuration ~
             render_modes = false,
             -- How to handle footnote links, start with a '^'.
             footnote = {
+                -- Turn on / off footnote rendering.
+                enabled = true,
                 -- Replace value with superscript equivalent.
                 superscript = true,
-                -- Added before link content when converting to superscript.
+                -- Added before link content.
                 prefix = '',
-                -- Added after link content when converting to superscript.
+                -- Added after link content.
                 suffix = '',
             },
             -- Inlined with 'image' elements.
@@ -1333,11 +1335,13 @@ Link Configuration ~
             render_modes = false,
             -- How to handle footnote links, start with a '^'.
             footnote = {
+                -- Turn on / off footnote rendering.
+                enabled = true,
                 -- Replace value with superscript equivalent.
                 superscript = true,
-                -- Added before link content when converting to superscript.
+                -- Added before link content.
                 prefix = '',
-                -- Added after link content when converting to superscript.
+                -- Added after link content.
                 suffix = '',
             },
             -- Inlined with 'image' elements.

lua/render-markdown/health.lua

@@ -5,7 +5,7 @@ local state = require('render-markdown.state')
 local M = {}
 
 ---@private
-M.version = '8.1.2'
+M.version = '8.1.3'
 
 function M.check()
     M.start('version')

lua/render-markdown/init.lua

@@ -110,6 +110,7 @@ local M = {}
 ---@field highlight? string
 
 ---@class (exact) render.md.UserFootnote
+---@field enabled? boolean
 ---@field superscript? boolean
 ---@field prefix? string
 ---@field suffix? string
@@ -789,11 +790,13 @@ M.default_config = {
         render_modes = false,
         -- How to handle footnote links, start with a '^'.
         footnote = {
+            -- Turn on / off footnote rendering.
+            enabled = true,
             -- Replace value with superscript equivalent.
             superscript = true,
-            -- Added before link content when converting to superscript.
+            -- Added before link content.
             prefix = '',
-            -- Added after link content when converting to superscript.
+            -- Added after link content.
             suffix = '',
         },
         -- Inlined with 'image' elements.

lua/render-markdown/lib/converter.lua

@@ -75,7 +75,7 @@ M.superscripts = {
 
 ---@param s string
 ---@return string?
-function M.to_superscript(s)
+function M.superscript(s)
     local chars = {}
     for char in s:gmatch('.') do
         char = M.superscripts[char]

lua/render-markdown/render/shortcut.lua

@@ -159,17 +159,15 @@ function Render:footnote(text)
     if self.context:skip(self.link) then
         return
     end
-
     local footnote = self.link.footnote
-    if not footnote.superscript then
+    if not footnote.enabled then
         return
     end
-
-    local value = Converter.to_superscript(footnote.prefix .. text .. footnote.suffix)
+    local body = footnote.prefix .. text .. footnote.suffix
+    local value = not footnote.superscript and body or Converter.superscript(body)
     if value == nil then
         return
     end
-
     self.marks:add_over('link', self.node, {
         virt_text = { { value, self.link.highlight } },
         virt_text_pos = 'inline',

lua/render-markdown/state.lua

@@ -259,7 +259,10 @@ function M.validate()
                 component_rules(link)
                     :type({ 'image', 'email', 'hyperlink', 'highlight' }, 'string')
                     :nested('footnote', function(footnote)
-                        footnote:type('superscript', 'boolean'):type({ 'prefix', 'suffix' }, 'string'):check()
+                        footnote
+                            :type({ 'enabled', 'superscript' }, 'boolean')
+                            :type({ 'prefix', 'suffix' }, 'string')
+                            :check()
                     end)
                     :nested('wiki', function(wiki)
                         wiki:type({ 'icon', 'highlight' }, 'string'):type('body', 'function'):check()

lua/render-markdown/types.lua

@@ -65,6 +65,7 @@
 ---@field highlight string
 
 ---@class (exact) render.md.Footnote
+---@field enabled boolean
 ---@field superscript boolean
 ---@field prefix string
 ---@field suffix string