feat: make winblend configurable (#1861)

doc/cmp.txt

@@ -696,6 +696,12 @@ window.{completion,documentation}.border~
 window.{completion,documentation}.winhighlight~
   `string | cmp.WinhighlightConfig`
   Specify the window's winhighlight option.
+  See |nvim_open_win|.
+
+                     *cmp-config.window.{completion,documentation}.winblend*
+window.{completion,documentation}.winblend~
+  `string | cmp.WinhighlightConfig`
+  Specify the window's winblend option.
   See |nvim_open_win|.
 
                            *cmp-config.window.{completion,documentation}.zindex*

lua/cmp/config/default.lua

@@ -107,6 +107,7 @@ return function()
       completion = {
         border = { '', '', '', '', '', '', '', '' },
         winhighlight = 'Normal:Pmenu,FloatBorder:Pmenu,CursorLine:PmenuSel,Search:None',
+        winblend = vim.o.pumblend,
         scrolloff = 0,
         col_offset = 0,
         side_padding = 1,
@@ -117,6 +118,7 @@ return function()
         max_width = math.floor((WIDE_HEIGHT * 2) * (vim.o.columns / (WIDE_HEIGHT * 2 * 16 / 9))),
         border = { '', '', '', ' ', '', '', '', ' ' },
         winhighlight = 'FloatBorder:NormalFloat',
+        winblend = vim.o.pumblend,
       },
     },
   }

lua/cmp/types/cmp.lua

@@ -121,6 +121,7 @@ cmp.ItemField = {
 ---@class cmp.WindowOptions
 ---@field public border? string|string[]
 ---@field public winhighlight? string
+---@field public winblend? number
 ---@field public zindex? integer|nil
 
 ---@class cmp.CompletionWindowOptions: cmp.WindowOptions

lua/cmp/view/custom_entries_view.lua

@@ -201,7 +201,7 @@ custom_entries_view.open = function(self, offset, entries)
   end
 
   -- Apply window options (that might be changed) on the custom completion menu.
-  self.entries_win:option('winblend', vim.o.pumblend)
+  self.entries_win:option('winblend', completion.winblend)
   self.entries_win:option('winhighlight', completion.winhighlight)
   self.entries_win:option('scrolloff', completion.scrolloff)
   self.entries_win:open({

lua/cmp/view/docs_view.lua

@@ -100,7 +100,7 @@ docs_view.open = function(self, e, view)
   end
 
   -- Render window.
-  self.window:option('winblend', vim.o.pumblend)
+  self.window:option('winblend', documentation.winblend)
   self.window:option('winhighlight', documentation.winhighlight)
   local style = {
     relative = 'editor',