feat(#2349): add "right_align" option for renderer.icons.*_placement (#2839)

* feat(icon_placement): Allow right_align icon_placemente for decorator using ext_marks nvim api

* feat(icon_placement): Allow right_align icon_placemente for decorator using ext_marks nvim api

feat(icon_placement): Allow right_align icon_placemente for decorator using ext_marks nvim api

* feat(icon_placement): consolidate doc

---------

Co-authored-by: Alexander Courtis <alex@courtis.org>

lua/nvim-tree/renderer/builder.lua

@@ -60,6 +60,7 @@ function Builder:new()
     lines = {},
     markers = {},
     signs = {},
+    extmarks = {},
   }
   setmetatable(o, self)
   self.__index = self
@@ -228,6 +229,14 @@ function Builder:format_line(indent_markers, arrows, icon, name, node)
     add_to_end(line, M.decorators[i]:icons_after(node))
   end
 
+  local rights = {}
+  for i = #M.decorators, 1, -1 do
+    add_to_end(rights, M.decorators[i]:icons_right_align(node))
+  end
+  if #rights > 0 then
+    self.extmarks[self.index] = rights
+  end
+
   return line
 end
 

lua/nvim-tree/renderer/decorator/init.lua

@@ -74,6 +74,17 @@ function Decorator:icons_after(node)
   return self:calculate_icons(node)
 end
 
+---Icons when ICON_PLACEMENT.right_align
+---@param node Node
+---@return HighlightedString[]|nil icons
+function Decorator:icons_right_align(node)
+  if not self.enabled or self.icon_placement ~= ICON_PLACEMENT.right_align then
+    return
+  end
+
+  return self:calculate_icons(node)
+end
+
 ---Maybe icons, optionally implemented
 ---@protected
 ---@param _ Node

lua/nvim-tree/renderer/init.lua

@@ -18,7 +18,7 @@ local namespace_id = vim.api.nvim_create_namespace "NvimTreeHighlights"
 ---@param lines string[]
 ---@param hl_args AddHighlightArgs[]
 ---@param signs string[]
-local function _draw(bufnr, lines, hl_args, signs)
+local function _draw(bufnr, lines, hl_args, signs, extmarks)
   if vim.fn.has "nvim-0.10" == 1 then
     vim.api.nvim_set_option_value("modifiable", true, { buf = bufnr })
   else
@@ -38,6 +38,15 @@ local function _draw(bufnr, lines, hl_args, signs)
   for i, sign_name in pairs(signs) do
     vim.fn.sign_place(0, SIGN_GROUP, sign_name, bufnr, { lnum = i + 1 })
   end
+  for i, extname in pairs(extmarks) do
+    for _, mark in ipairs(extname) do
+      vim.api.nvim_buf_set_extmark(bufnr, namespace_id, i, -1, {
+        virt_text = { { mark.str, mark.hl } },
+        virt_text_pos = "right_align",
+        hl_mode = "combine",
+      })
+    end
+  end
 end
 
 function M.render_hl(bufnr, hl)
@@ -67,7 +76,7 @@ function M.draw()
 
   local builder = Builder:new():build()
 
-  _draw(bufnr, builder.lines, builder.hl_args, builder.signs)
+  _draw(bufnr, builder.lines, builder.hl_args, builder.signs, builder.extmarks)
 
   if cursor and #builder.lines >= cursor[1] then
     vim.api.nvim_win_set_cursor(view.get_winnr() or 0, cursor)