feat(menu): scrollbar customization options

Adds the ability to hide the scrollbar's background, or
to disable it entirely.

README.md

@@ -443,6 +443,13 @@ https://github.com/Bekaboo/dropbar.nvim/assets/76579810/e8c1ac26-0321-4762-9975-
           right = 1,
         },
       },
+      -- Menu scrollbar options
+      scrollbar = {
+        enable = true,
+        -- The background / gutter of the scrollbar
+        -- When false, only the scrollbar thumb is shown.
+        background = true
+      },
       ---@type table<string, string|function|table<string, string|function>>
     keymaps = {
       ['<LeftMouse>'] = function()
@@ -515,8 +522,13 @@ https://github.com/Bekaboo/dropbar.nvim/assets/76579810/e8c1ac26-0321-4762-9975-
         ---@param menu dropbar_menu_t
         col = function(menu)
           if menu.prev_menu then
-            return menu.prev_menu._win_configs.width
-              + (menu.prev_menu.scrollbar and 1 or 0)
+            local offset = 0
+            if
+              menu.prev_menu.scrollbar and M.opts.menu.scrollbar.background
+            then
+              offset = 1
+            end
+            return menu.prev_menu._win_configs.width + offset
           end
           local mouse = vim.fn.getmousepos()
           local bar = utils.bar.get({ win = menu.prev_win })
@@ -1123,6 +1135,18 @@ menu:
       end
     },
     ```
+
+- `opts.menu.scrollbar`: `table<string, boolean>`
+  - Scrollbar configuration for the menu.
+  - Default:
+  ```lua
+  {
+    enable = true,
+    -- if false, only the scrollbar thumb will be shown
+    background = true
+  }
+  ```
+
 - `opts.menu.win_configs`: `table<string, dropbar_menu_win_config_opts_t>`
   - Window configurations for the menu, see `:h nvim_open_win()`
   - Each config key in `opts.menu.win_configs` accepts either a plain value

doc/dropbar.txt

@@ -541,6 +541,16 @@ the menu:
 	      end
 	    },
 <
+- `opts.menu.scrollbar`: `table<string, boolean>`
+    - Scrollbar configuration for the menu.
+    - Default: >lua
+    {
+      enable = true,
+      -- if false, only the scrollbar thumb will be shown
+      background = true
+    }
+<
+
 - `opts.menu.win_configs`: `table<string, dropbar_menu_win_config_opts_t>`
     - Window configurations for the menu, see `:h nvim_open_win()`
     - Each config key in `opts.menu.win_configs` accepts either a plain value

lua/dropbar/configs.lua

@@ -209,6 +209,13 @@ M.opts = {
         right = 1,
       },
     },
+    -- Menu scrollbar options
+    scrollbar = {
+      enable = true,
+      -- The background / gutter of the scrollbar
+      -- When false, only the thumb is shown.
+      background = true,
+    },
     ---@type table<string, string|function|table<string, string|function>>
     keymaps = {
       ['<LeftMouse>'] = function()
@@ -281,8 +288,11 @@ M.opts = {
       ---@param menu dropbar_menu_t
       col = function(menu)
         if menu.prev_menu then
-          return menu.prev_menu._win_configs.width
-            + (menu.prev_menu.scrollbar and 1 or 0)
+          local offset = 0
+          if menu.prev_menu.scrollbar and M.opts.menu.scrollbar.background then
+            offset = 1
+          end
+          return menu.prev_menu._win_configs.width + offset
         end
         local mouse = vim.fn.getmousepos()
         local bar = utils.bar.get({ win = menu.prev_win })

lua/dropbar/menu.lua

@@ -189,7 +189,7 @@ end
 ---@field prev_cursor integer[]? previous cursor position
 ---@field symbol_previewed dropbar_symbol_t? symbol being previewed
 ---@field fzf_state fzf_state_t? fuzzy-finding state, or nil if not currently fuzzy-finding
----@field scrollbar { thumb: integer, sbar: integer }? scrollbar window handlers
+---@field scrollbar { thumb: integer, background: integer }? scrollbar window handlers
 local dropbar_menu_t = {}
 dropbar_menu_t.__index = dropbar_menu_t
 
@@ -538,6 +538,7 @@ function dropbar_menu_t:update_scrollbar()
     or not self.buf
     or not vim.api.nvim_win_is_valid(self.win)
     or not vim.api.nvim_buf_is_valid(self.buf)
+    or not configs.opts.menu.scrollbar.enable
   then
     return
   end
@@ -568,26 +569,31 @@ function dropbar_menu_t:update_scrollbar()
     self.scrollbar = {}
 
     local win_configs = {
-      row = 0,
-      col = menu_win_configs.width,
+      row = offset,
+      col = menu_win_configs.width
+        - (configs.opts.menu.scrollbar.background and 0 or 1),
       width = 1,
       height = menu_win_configs.height,
       style = 'minimal',
       border = 'none',
       relative = 'win',
       win = self.win,
-      zindex = menu_win_configs.zindex,
+      zindex = menu_win_configs.zindex
+        + (configs.opts.menu.scrollbar.background and 0 or 1),
     }
-    self.scrollbar.sbar = vim.api.nvim_open_win(
-      vim.api.nvim_create_buf(false, true),
-      false,
-      win_configs
-    )
-    vim.wo[self.scrollbar.sbar].winhl = 'NormalFloat:DropBarMenuSbar'
 
-    win_configs.row = offset
-    win_configs.height = thumb_height
-    win_configs.zindex = menu_win_configs.zindex + 1
+    if configs.opts.menu.scrollbar.background then
+      win_configs.row = 0
+      win_configs.height = menu_win_configs.height
+      win_configs.zindex = win_configs.zindex - 1
+      self.scrollbar.background = vim.api.nvim_open_win(
+        vim.api.nvim_create_buf(false, true),
+        false,
+        win_configs
+      )
+      vim.wo[self.scrollbar.background].winhl = 'NormalFloat:DropBarMenuSbar'
+    end
+
     self.scrollbar.thumb = vim.api.nvim_open_win(
       vim.api.nvim_create_buf(false, true),
       false,
@@ -607,8 +613,11 @@ function dropbar_menu_t:close_scrollbar()
   if vim.api.nvim_win_is_valid(self.scrollbar.thumb) then
     vim.api.nvim_win_close(self.scrollbar.thumb, true)
   end
-  if vim.api.nvim_win_is_valid(self.scrollbar.sbar) then
-    vim.api.nvim_win_close(self.scrollbar.sbar, true)
+  if
+    self.scrollbar.background
+    and vim.api.nvim_win_is_valid(self.scrollbar.background)
+  then
+    vim.api.nvim_win_close(self.scrollbar.background, true)
   end
   self.scrollbar = nil
 end