Restore filetype setting

doc/cmp.txt

@@ -12,6 +12,7 @@ Function                                                          |cmp-function|
 Mapping                                                            |cmp-mapping|
 Command                                                            |cmp-command|
 Highlight                                                        |cmp-highlight|
+FileType                                                          |cmp-filetype|
 Autocmd                                                            |cmp-autocmd|
 Config                                                              |cmp-config|
 Config Helper                                                |cmp-config-helper|
@@ -312,6 +313,8 @@ There are also builtin mapping helper functions you can use:
 Built-in mapping helpers are only available as a configuration option.
 If you want to call nvim-cmp features directly, please use |cmp-function| instead.
 
+
+
 ==============================================================================
 Command                                                            *cmp-command*
 
@@ -321,6 +324,8 @@ Command                                                            *cmp-command*
   For example, `cmp-nvim-lsp` registers itself on InsertEnter autocommand
   so the status will be shown as `unknown` when running the command.
 
+
+
 ==============================================================================
 Highlight                                                        *cmp-highlight*
 
@@ -351,6 +356,15 @@ NOTE: `kind` is a symbol after each completion option.
 *CmpItemMenu*
   The menu field's highlight group.
 
+==============================================================================
+FileType                                                          *cmp-filetype*
+
+*cmp_menu*
+  The completion menu buffer's filetype.
+
+*cmp_docs*
+  The documentation window buffer's filetype.
+
 ==============================================================================
 Autocmd                                                            *cmp-autocmd*
 

lua/cmp/view/custom_entries_view.lua

@@ -37,6 +37,7 @@ custom_entries_view.new = function()
   -- always rendered one column wide, which removes the unpredictability coming
   -- from variable width of the tab character.
   self.entries_win:buffer_option('tabstop', 1)
+  self.entries_win:buffer_option('filetype', 'cmp_menu')
   self.event = event.new()
   self.offset = -1
   self.active = false

lua/cmp/view/docs_view.lua

@@ -16,6 +16,7 @@ docs_view.new = function()
   self.window:option('linebreak', true)
   self.window:option('scrolloff', 0)
   self.window:option('wrap', true)
+  self.window:buffer_option('filetype', 'cmp_docs')
   return self
 end