feat(code): width = block (#88)

* merge

* refactor: cleanup

* fix: no need to subtract width from block pad

* fix: add left_pad to block width

* fix: right_pad = 0 by default

* fix: extmark priority

Author: folke

Diff for: lua/render-markdown/handler/markdown.lua

@@ -177,6 +177,17 @@ M.render_code = function(buf, info)
     if start_row == end_row - 1 then
         return marks
     end
+
+    local width = util.get_width(buf)
+    if code.width == 'block' then
+        width = 0
+        local lines = vim.api.nvim_buf_get_lines(buf, start_row, end_row, false)
+        for _, line in ipairs(lines) do
+            width = math.max(width, str.width(line))
+        end
+    end
+    width = width + code.right_pad + code.left_pad
+
     if code.border == 'thin' then
         local code_start = ts.child(buf, info, 'fenced_code_block_delimiter', info.start_row)
         if #marks == 0 and ts.hidden(buf, code_info) and ts.hidden(buf, code_start) then
@@ -187,7 +198,7 @@ M.render_code = function(buf, info)
                 start_row = info.start_row,
                 start_col = info.start_col,
                 opts = {
-                    virt_text = { { code.above:rep(util.get_width(buf)), colors.inverse(code.highlight) } },
+                    virt_text = { { code.above:rep(width), colors.inverse(code.highlight) } },
                     virt_text_pos = 'overlay',
                 },
             }
@@ -202,7 +213,7 @@ M.render_code = function(buf, info)
                 start_row = info.end_row - 1,
                 start_col = info.start_col,
                 opts = {
-                    virt_text = { { code.below:rep(util.get_width(buf)), colors.inverse(code.highlight) } },
+                    virt_text = { { code.below:rep(width), colors.inverse(code.highlight) } },
                     virt_text_pos = 'overlay',
                 },
             }
@@ -222,6 +233,27 @@ M.render_code = function(buf, info)
         },
     }
     list.add(marks, background_mark)
+
+    if code.width == 'block' then
+        -- overwrite anything beyond block width + right_pad with Normal
+        local pad = str.pad('', vim.o.columns * 2)
+        for row = start_row, code.border == 'thin' and end_row or end_row - 1 do
+            ---@type render.md.Mark
+            local block_background_mark = {
+                conceal = false,
+                start_row = row,
+                start_col = 0,
+                opts = {
+                    priority = 0,
+                    hl_mode = 'combine',
+                    virt_text = { { pad, 'Normal' } },
+                    virt_text_win_col = width,
+                },
+            }
+            list.add(marks, block_background_mark)
+        end
+    end
+
     -- Requires inline extmarks
     if not util.has_10 or code.left_pad <= 0 then
         return marks

Diff for: lua/render-markdown/init.lua

@@ -69,6 +69,8 @@ local M = {}
 ---@field public sign? boolean
 ---@field public style? 'full'|'normal'|'language'|'none'
 ---@field public left_pad? integer
+---@field public right_pad? integer
+---@field public width? 'full'|'block'
 ---@field public border? 'thin'|'thick'
 ---@field public above? string
 ---@field public below? string
@@ -244,6 +246,9 @@ M.default_config = {
         style = 'full',
         -- Amount of padding to add to the left of code blocks
         left_pad = 0,
+        -- Amount of padding to add to the right of code blocks
+        -- when width is 'block'
+        right_pad = 0,
         -- Determins how the top / bottom of code block are rendered:
         --  thick: use the same highlight as the code body
         --  thin: when lines are empty overlay the above & below icons
@@ -255,6 +260,10 @@ M.default_config = {
         -- Highlight for code blocks & inline code
         highlight = 'RenderMarkdownCode',
         highlight_inline = 'RenderMarkdownCodeInline',
+        -- Width of the code block background:
+        -- * full: full width of the window
+        -- * block: width of the code block
+        width = 'full',
     },
     dash = {
         -- Turn on / off thematic break rendering

Diff for: lua/render-markdown/types.lua

@@ -53,7 +53,9 @@
 ---@field public enabled boolean
 ---@field public sign boolean
 ---@field public style 'full'|'normal'|'language'|'none'
+---@field public width 'full'|'block'
 ---@field public left_pad integer
+---@field public right_pad integer
 ---@field public border 'thin'|'thick'
 ---@field public above string
 ---@field public below string