Always pass response for is_error function (#86)

autoload/lsp/client.vim

@@ -227,8 +227,8 @@ function! s:lsp_get_last_request_id(id) abort
     return s:clients[a:id]['request_sequence']
 endfunction
 
-function! s:lsp_is_error(notification) abort
-    return has_key(a:notification, 'error')
+function! s:lsp_is_error(obj_or_response) abort
+    return has_key(a:obj_or_response, 'error')
 endfunction
 
 function! s:is_server_instantiated_notification(notification) abort
@@ -257,8 +257,8 @@ function! lsp#client#get_last_request_id(client_id) abort
     return s:lsp_get_last_request_id(a:client_id)
 endfunction
 
-function! lsp#client#is_error(notification) abort
-    return s:lsp_is_error(a:notification)
+function! lsp#client#is_error(obj_or_response) abort
+    return s:lsp_is_error(a:obj_or_response)
 endfunction
 
 function! lsp#client#is_server_instantiated_notification(notification) abort

autoload/lsp/ui/vim.vim

@@ -282,7 +282,7 @@ function! s:handle_symbol(server, last_req_id, type, data) abort
         return
     endif
 
-    if lsp#client#is_error(a:data)
+    if lsp#client#is_error(a:data['response'])
         call s:error_msg('Failed to retrieve '. a:type . ' for ' . a:server)
         return
     endif
@@ -306,7 +306,7 @@ function! s:handle_location(ctx, server, type, data) abort "ctx = {counter, list
 
     let a:ctx['counter'] = a:ctx['counter'] - 1
 
-    if lsp#client#is_error(a:data)
+    if lsp#client#is_error(a:data['response'])
         call s:error_msg('Failed to retrieve '. a:type . ' for ' . a:server)
     else
         let a:ctx['list'] = a:ctx['list'] + lsp#ui#vim#utils#locations_to_loc_list(a:data)
@@ -337,7 +337,7 @@ function! s:handle_hover(server, last_req_id, type, data) abort
         return
     endif
 
-    if lsp#client#is_error(a:data)
+    if lsp#client#is_error(a:data['response'])
         call s:error_msg('Failed to retrieve '. a:type . ' for ' . a:server)
         return
     endif