feat: add config option for a tree indent width

add 'indent_width' option to configure visible indent for tree nesting
levels (default is 2).

Author: mivort

doc/nvim-tree-lua.txt

@@ -213,6 +213,7 @@ Subsequent calls to setup will replace the previous configuration.
         full_name = false,
         highlight_opened_files = "none",
         root_folder_modifier = ":~",
+        indent_width = 2,
         indent_markers = {
           enable = false,
           inline_arrows = true,
@@ -709,6 +710,10 @@ UI rendering setup
     available options.
       Type: `string`, Default: `":~"`
 
+    *nvim-tree.renderer.indent_width*
+    Number of spaces for an each tree nesting level.
+      Type: `number`, Default: `2`
+
     *nvim-tree.renderer.indent_markers*
     Configuration options for tree indent markers.
 

lua/nvim-tree.lua

@@ -476,6 +476,7 @@ local DEFAULT_OPTS = { -- BEGIN_DEFAULT_OPTS
     full_name = false,
     highlight_opened_files = "none",
     root_folder_modifier = ":~",
+    indent_width = 2,
     indent_markers = {
       enable = false,
       inline_arrows = true,

lua/nvim-tree/renderer/builder.lua

@@ -258,9 +258,9 @@ function Builder:_build_line(node, idx, num_children)
   self.index = self.index + 1
 
   if node.open then
-    self.depth = self.depth + 2
+    self.depth = self.depth + 1
     self:build(node)
-    self.depth = self.depth - 2
+    self.depth = self.depth - 1
   end
 end
 

lua/nvim-tree/renderer/components/padding.lua

@@ -25,30 +25,30 @@ local function get_padding_indent_markers(depth, idx, nodes_number, markers, wit
 
   if depth > 0 then
     local has_folder_sibling = check_siblings_for_folder(node, with_arrows)
-    local rdepth = depth / 2
-    markers[rdepth] = idx ~= nodes_number
-    for i = 1, rdepth do
+    local indent = string.rep(" ", M.config.indent_width - 1)
+    markers[depth] = idx ~= nodes_number
+    for i = 1, depth do
       local glyph
-      if idx == nodes_number and i == rdepth then
+      if idx == nodes_number and i == depth then
         glyph = M.config.indent_markers.icons.corner
-      elseif markers[i] and i == rdepth then
+      elseif markers[i] and i == depth then
         glyph = M.config.indent_markers.icons.item
       elseif markers[i] then
         glyph = M.config.indent_markers.icons.edge
       else
         glyph = M.config.indent_markers.icons.none
       end
 
-      if not with_arrows or (inline_arrows and (rdepth ~= i or not node.nodes)) then
-        padding = padding .. glyph .. " "
+      if not with_arrows or (inline_arrows and (depth ~= i or not node.nodes)) then
+        padding = padding .. glyph .. indent
       elseif inline_arrows then
         padding = padding
-      elseif idx == nodes_number and i == rdepth and has_folder_sibling then
-        padding = padding .. base_padding .. glyph .. "── "
-      elseif rdepth == i and not node.nodes and has_folder_sibling then
-        padding = padding .. base_padding .. glyph .. " " .. base_padding
+      elseif idx == nodes_number and i == depth and has_folder_sibling then
+        padding = padding .. base_padding .. glyph .. "──" .. indent
+      elseif depth == i and not node.nodes and has_folder_sibling then
+        padding = padding .. base_padding .. glyph .. indent .. base_padding
       else
-        padding = padding .. base_padding .. glyph .. " "
+        padding = padding .. base_padding .. glyph .. indent
       end
     end
   end
@@ -71,11 +71,12 @@ function M.get_padding(depth, idx, nodes_number, node, markers)
   local show_arrows = M.config.icons.show.folder_arrow
   local show_markers = M.config.indent_markers.enable
   local inline_arrows = M.config.indent_markers.inline_arrows
+  local indent_width = M.config.indent_width
 
   if show_markers then
     padding = padding .. get_padding_indent_markers(depth, idx, nodes_number, markers, show_arrows, inline_arrows, node)
   else
-    padding = padding .. string.rep(" ", depth)
+    padding = padding .. string.rep(" ", depth * indent_width)
   end
 
   if show_arrows then