Add option to request synchronized .

Also add LspDocumentFormatSync. This can be used for autocmd before
saving the file.

Author: mattn

autoload/lsp/client.vim

@@ -226,7 +226,11 @@ function! s:lsp_send(id, opts, type) abort " opts = { method, params?, on_notifi
     call async#job#send(a:id, l:payload)
 
     if (a:type == s:send_type_request)
-        return l:request['id']
+        let l:id = l:request['id']
+        if get(a:opts, 'sync', 0) !=# 0
+            call async#job#wait([l:id])
+        endif
+        return l:id
     else
         return 0
     endif

autoload/lsp/ui/vim.vim

@@ -136,7 +136,7 @@ function! lsp#ui#vim#rename() abort
     echo ' ... Renaming ...'
 endfunction
 
-function! lsp#ui#vim#document_format() abort
+function! s:document_format(sync) abort
     let l:servers = filter(lsp#get_whitelisted_servers(), 'lsp#capabilities#has_document_formatting_provider(v:val)')
     let s:last_req_id = s:last_req_id + 1
 
@@ -156,12 +156,21 @@ function! lsp#ui#vim#document_format() abort
         \       'insertSpaces': getbufvar(bufnr('%'), '&expandtab') ? v:true : v:false,
         \   },
         \ },
+        \ 'sync': a:sync,
         \ 'on_notification': function('s:handle_text_edit', [l:server, s:last_req_id, 'document format']),
         \ })
 
     echo 'Formatting document ...'
 endfunction
 
+function! lsp#ui#vim#document_format_sync() abort
+    return s:document_format(1)
+endfunction
+
+function! lsp#ui#vim#document_format() abort
+    return s:document_format(0)
+endfunction
+
 function! s:get_visual_selection_pos() abort
     " https://groups.google.com/d/msg/vim_dev/oCUQzO3y8XE/vfIMJiHCHtEJ
     " https://stackoverflow.com/a/6271254

plugin/lsp.vim

@@ -33,6 +33,7 @@ command! LspReferences call lsp#ui#vim#references()
 command! LspRename call lsp#ui#vim#rename()
 command! LspWorkspaceSymbol call lsp#ui#vim#workspace_symbol()
 command! LspDocumentFormat call lsp#ui#vim#document_format()
+command! LspDocumentFormatSync call lsp#ui#vim#document_format_sync()
 command! -range LspDocumentRangeFormat call lsp#ui#vim#document_range_format()
 command! LspImplementation call lsp#ui#vim#implementation()
 command! LspTypeDefinition call lsp#ui#vim#type_definition()