rename: add support for gopls rename

Author: bhcleek

autoload/go/rename.vim

@@ -23,23 +23,26 @@ function! go#rename#Rename(bang, ...) abort
   let l:bin = go#config#RenameCommand()
 
   " return with a warning if the bin doesn't exist
-  let bin_path = go#path#CheckBinPath(l:bin)
+  let bin_path = go#path#CheckBinPath(substitute(l:bin, 'gopls rename$', 'gopls', ''))
   if empty(bin_path)
     return
   endif
 
-  let fname = expand('%:p')
-  let pos = go#util#OffsetCursor()
-  let offset = printf('%s:#%d', fname, pos)
-
   if l:bin == 'gopls'
     call go#lsp#Rename(to_identifier)
     return
   endif
 
+  let fname = expand('%:p')
+  let pos = go#util#OffsetCursor()
+
   let args = []
   if l:bin == 'gorename'
+    let offset = printf('%s:#%d', fname, pos)
     let l:args = extend(l:args, ['-tags', go#config#BuildTags(), '-offset', offset, '-to', to_identifier])
+  elseif l:bin == 'gopls rename'
+    let offset = printf('%s:#%d', fname, pos)
+    let l:args = extend(l:args, ['rename', '-write', offset, to_identifier])
   else
     call go#util#EchoWarning('unexpected rename command')
   endif

doc/vim-go.txt

@@ -1676,7 +1676,7 @@ default it is set to edit.
                                                        *'g:go_rename_command'*
 
 Use this option to define which tool is used to rename. By default `gopls`
-is used. Valid options are `gorename` and `gopls`.
+is used. Valid options are `gopls`, `gopls rename`, and `gorename`.
 >
   let g:go_rename_command = 'gopls'
 <