feat: Allow custom link icons based on lua patterns

## Details

Requested: #117

Similar to callouts and checkbox states this change allows link
destinations to be matched against configured patterns when selecting an
icon rather than using the same one everytime. For instance web links
now use a little globe rather than the default chain link icon.

More defaults can be added in if requested, for now mostly to allow
individuals to use as they wish.

Author: MeanderingProgrammer

README.md

@@ -405,10 +405,20 @@ require('render-markdown').setup({
         enabled = true,
         -- Inlined with 'image' elements
         image = '󰥶 ',
-        -- Inlined with 'inline_link' elements
+        -- Fallback icon for 'inline_link' elements
         hyperlink = '󰌹 ',
-        -- Applies to the inlined icon
+        -- Applies to the fallback inlined icon
         highlight = 'RenderMarkdownLink',
+        -- Define custom destination patterns so icons can quickly inform you of what a link
+        -- contains. Applies to 'inline_link' and wikilink nodes.
+        -- Can specify as many additional values as you like following the 'web' pattern below
+        --   The key in this case 'web' is for healthcheck and to allow users to change its values
+        --   'pattern': Matched against the destination text see :h lua-pattern
+        --   'icon': Gets inlined before the link text
+        --   'highlight': Highlight for the 'icon'
+        custom = {
+            web = { pattern = '^http[s]?://', icon = '󰖟 ', highlight = 'RenderMarkdownLink' },
+        },
     },
     sign = {
         -- Turn on / off sign rendering
@@ -728,10 +738,20 @@ require('render-markdown').setup({
         enabled = true,
         -- Inlined with 'image' elements
         image = '󰥶 ',
-        -- Inlined with 'inline_link' elements
+        -- Fallback icon for 'inline_link' elements
         hyperlink = '󰌹 ',
-        -- Applies to the inlined icon
+        -- Applies to the fallback inlined icon
         highlight = 'RenderMarkdownLink',
+        -- Define custom destination patterns so icons can quickly inform you of what a link
+        -- contains. Applies to 'inline_link' and wikilink nodes.
+        -- Can specify as many additional values as you like following the 'web' pattern below
+        --   The key in this case 'web' is for healthcheck and to allow users to change its values
+        --   'pattern': Matched against the destination text see :h lua-pattern
+        --   'icon': Gets inlined before the link text
+        --   'highlight': Highlight for the 'icon'
+        custom = {
+            web = { pattern = '^http[s]?://', icon = '󰖟 ', highlight = 'RenderMarkdownLink' },
+        },
     },
 })
 ```

doc/render-markdown.txt

@@ -438,10 +438,20 @@ Full Default Configuration ~
             enabled = true,
             -- Inlined with 'image' elements
             image = '󰥶 ',
-            -- Inlined with 'inline_link' elements
+            -- Fallback icon for 'inline_link' elements
             hyperlink = '󰌹 ',
-            -- Applies to the inlined icon
+            -- Applies to the fallback inlined icon
             highlight = 'RenderMarkdownLink',
+            -- Define custom destination patterns so icons can quickly inform you of what a link
+            -- contains. Applies to 'inline_link' and wikilink nodes.
+            -- Can specify as many additional values as you like following the 'web' pattern below
+            --   The key in this case 'web' is for healthcheck and to allow users to change its values
+            --   'pattern': Matched against the destination text see :h lua-pattern
+            --   'icon': Gets inlined before the link text
+            --   'highlight': Highlight for the 'icon'
+            custom = {
+                web = { pattern = '^http[s]?://', icon = '󰖟 ', highlight = 'RenderMarkdownLink' },
+            },
         },
         sign = {
             -- Turn on / off sign rendering
@@ -768,10 +778,20 @@ LINKS                                            *render-markdown-setup-links*
             enabled = true,
             -- Inlined with 'image' elements
             image = '󰥶 ',
-            -- Inlined with 'inline_link' elements
+            -- Fallback icon for 'inline_link' elements
             hyperlink = '󰌹 ',
-            -- Applies to the inlined icon
+            -- Applies to the fallback inlined icon
             highlight = 'RenderMarkdownLink',
+            -- Define custom destination patterns so icons can quickly inform you of what a link
+            -- contains. Applies to 'inline_link' and wikilink nodes.
+            -- Can specify as many additional values as you like following the 'web' pattern below
+            --   The key in this case 'web' is for healthcheck and to allow users to change its values
+            --   'pattern': Matched against the destination text see :h lua-pattern
+            --   'icon': Gets inlined before the link text
+            --   'highlight': Highlight for the 'icon'
+            custom = {
+                web = { pattern = '^http[s]?://', icon = '󰖟 ', highlight = 'RenderMarkdownLink' },
+            },
         },
     })
 <

lua/render-markdown/component.lua

@@ -49,4 +49,16 @@ function M.checkbox(config, text, comparison)
     return nil
 end
 
+---@param config render.md.BufferConfig
+---@param text string
+---@return render.md.LinkComponent?
+function M.link(config, text)
+    for _, component in pairs(config.link.custom) do
+        if text:find(component.pattern) then
+            return component
+        end
+    end
+    return nil
+end
+
 return M

lua/render-markdown/handler/markdown_inline.lua

@@ -7,24 +7,34 @@ local str = require('render-markdown.str')
 local ts = require('render-markdown.ts')
 local util = require('render-markdown.util')
 
----@class render.md.handler.MarkdownInline: render.md.Handler
-local M = {}
+---@class render.md.handler.buf.MarkdownInline
+---@field private buf integer
+---@field private config render.md.BufferConfig
+local Handler = {}
+Handler.__index = Handler
 
----@param root TSNode
 ---@param buf integer
+---@return render.md.handler.buf.MarkdownInline
+function Handler.new(buf)
+    local self = setmetatable({}, Handler)
+    self.buf = buf
+    self.config = state.get_config(buf)
+    return self
+end
+
+---@param root TSNode
 ---@return render.md.Mark[]
-function M.parse(root, buf)
-    local config = state.get_config(buf)
+function Handler:parse(root)
     local marks = {}
-    context.get(buf):query(root, state.inline_query, function(capture, node)
-        local info = ts.info(node, buf)
+    context.get(self.buf):query(root, state.inline_query, function(capture, node)
+        local info = ts.info(node, self.buf)
         logger.debug_node_info(capture, info)
         if capture == 'code' then
-            list.add_mark(marks, M.code(config, info))
+            list.add_mark(marks, self:code(info))
         elseif capture == 'shortcut' then
-            list.add_mark(marks, M.shortcut(config, buf, info))
+            list.add_mark(marks, self:shortcut(info))
         elseif capture == 'link' then
-            list.add_mark(marks, M.link(config, buf, info))
+            list.add_mark(marks, self:link(info))
         else
             logger.unhandled_capture('inline', capture)
         end
@@ -33,11 +43,10 @@ function M.parse(root, buf)
 end
 
 ---@private
----@param config render.md.BufferConfig
 ---@param info render.md.NodeInfo
 ---@return render.md.Mark?
-function M.code(config, info)
-    local code = config.code
+function Handler:code(info)
+    local code = self.config.code
     if not code.enabled then
         return nil
     end
@@ -58,37 +67,33 @@ function M.code(config, info)
 end
 
 ---@private
----@param config render.md.BufferConfig
----@param buf integer
 ---@param info render.md.NodeInfo
 ---@return render.md.Mark?
-function M.shortcut(config, buf, info)
-    local callout = component.callout(config, info.text, 'exact')
+function Handler:shortcut(info)
+    local callout = component.callout(self.config, info.text, 'exact')
     if callout ~= nil then
-        return M.callout(config, buf, info, callout)
+        return self:callout(info, callout)
     end
-    local checkbox = component.checkbox(config, info.text, 'exact')
+    local checkbox = component.checkbox(self.config, info.text, 'exact')
     if checkbox ~= nil then
-        return M.checkbox(config, info, checkbox)
+        return self:checkbox(info, checkbox)
     end
-    local line = vim.api.nvim_buf_get_lines(buf, info.start_row, info.start_row + 1, false)[1]
+    local line = vim.api.nvim_buf_get_lines(self.buf, info.start_row, info.start_row + 1, false)[1]
     if line:find('[' .. info.text .. ']', 1, true) ~= nil then
-        return M.wiki_link(config, info)
+        return self:wiki_link(info)
     end
     return nil
 end
 
 ---@private
----@param config render.md.BufferConfig
----@param buf integer
 ---@param info render.md.NodeInfo
 ---@param callout render.md.CustomComponent
 ---@return render.md.Mark?
-function M.callout(config, buf, info, callout)
+function Handler:callout(info, callout)
     ---Support for overriding title: https://help.obsidian.md/Editing+and+formatting/Callouts#Change+the+title
     ---@return string, string?
     local function custom_title()
-        local content = ts.parent(buf, info, 'inline')
+        local content = ts.parent(self.buf, info, 'inline')
         if content ~= nil then
             local line = str.split(content.text, '\n')[1]
             if #line > #callout.raw and vim.startswith(line:lower(), callout.raw:lower()) then
@@ -100,7 +105,7 @@ function M.callout(config, buf, info, callout)
         return callout.rendered, nil
     end
 
-    if not config.quote.enabled then
+    if not self.config.quote.enabled then
         return nil
     end
     local text, conceal = custom_title()
@@ -120,16 +125,12 @@ function M.callout(config, buf, info, callout)
 end
 
 ---@private
----@param config render.md.BufferConfig
 ---@param info render.md.NodeInfo
 ---@param checkbox render.md.CustomComponent
 ---@return render.md.Mark?
-function M.checkbox(config, info, checkbox)
-    if not config.checkbox.enabled then
-        return nil
-    end
+function Handler:checkbox(info, checkbox)
     -- Requires inline extmarks
-    if not util.has_10 then
+    if not self.config.checkbox.enabled or not util.has_10 then
         return nil
     end
     ---@type render.md.Mark
@@ -148,20 +149,16 @@ function M.checkbox(config, info, checkbox)
 end
 
 ---@private
----@param config render.md.BufferConfig
 ---@param info render.md.NodeInfo
 ---@return render.md.Mark?
-function M.wiki_link(config, info)
-    local link = config.link
-    if not link.enabled then
-        return nil
-    end
+function Handler:wiki_link(info)
     -- Requires inline extmarks
-    if not util.has_10 then
+    if not self.config.link.enabled or not util.has_10 then
         return nil
     end
     local text = info.text:sub(2, -2)
-    local elements = str.split(text, '|')
+    local parts = str.split(text, '|')
+    local icon, highlight = self:destination_info(parts[1])
     ---@type render.md.Mark
     return {
         conceal = true,
@@ -170,37 +167,38 @@ function M.wiki_link(config, info)
         opts = {
             end_row = info.end_row,
             end_col = info.end_col + 1,
-            virt_text = { { link.hyperlink .. elements[#elements], link.highlight } },
+            virt_text = { { icon .. parts[#parts], highlight } },
             virt_text_pos = 'inline',
             conceal = '',
         },
     }
 end
 
 ---@private
----@param config render.md.BufferConfig
----@param buf integer
 ---@param info render.md.NodeInfo
 ---@return render.md.Mark?
-function M.link(config, buf, info)
-    local link = config.link
-    if not link.enabled then
-        return nil
-    end
+function Handler:link(info)
+    local link = self.config.link
     -- Requires inline extmarks
-    if not util.has_10 then
+    if not link.enabled or not util.has_10 then
         return nil
     end
-    local icon = nil
-    if vim.tbl_contains({ 'inline_link', 'full_reference_link' }, info.type) then
-        icon = link.hyperlink
+    local icon, highlight
+    if info.type == 'inline_link' then
+        local destination = ts.child(self.buf, info, 'link_destination')
+        if destination ~= nil then
+            icon, highlight = self:destination_info(destination.text)
+        else
+            icon, highlight = link.hyperlink, link.highlight
+        end
+    elseif info.type == 'full_reference_link' then
+        icon, highlight = link.hyperlink, link.highlight
     elseif info.type == 'image' then
-        icon = link.image
-    end
-    if icon == nil then
+        icon, highlight = link.image, link.highlight
+    else
         return nil
     end
-    context.get(buf):add_link(info, icon)
+    context.get(self.buf):add_link(info, icon)
     ---@type render.md.Mark
     return {
         conceal = true,
@@ -209,10 +207,32 @@ function M.link(config, buf, info)
         opts = {
             end_row = info.end_row,
             end_col = info.end_col,
-            virt_text = { { icon, link.highlight } },
+            virt_text = { { icon, highlight } },
             virt_text_pos = 'inline',
         },
     }
 end
 
+---@private
+---@param destination string
+---@return string, string
+function Handler:destination_info(destination)
+    local link_component = component.link(self.config, destination)
+    if link_component == nil then
+        return self.config.link.hyperlink, self.config.link.highlight
+    else
+        return link_component.icon, link_component.highlight
+    end
+end
+
+---@class render.md.handler.MarkdownInline: render.md.Handler
+local M = {}
+
+---@param root TSNode
+---@param buf integer
+---@return render.md.Mark[]
+function M.parse(root, buf)
+    return Handler.new(buf):parse(root)
+end
+
 return M

lua/render-markdown/health.lua

@@ -5,7 +5,7 @@ local M = {}
 
 ---@private
 ---@type string
-M.version = '5.1.3'
+M.version = '5.1.4'
 
 function M.check()
     vim.health.start('markdown.nvim [version]')