Merge pull request nvim-treesitter#15 from theHamsta/fix-nil-reference

Fix: Add nil check to current_scope

Author: steelsojka

lua/nvim-treesitter-refactor/highlight_current_scope.lua

@@ -15,10 +15,12 @@ function M.highlight_current_scope(bufnr)
   local node_at_point = ts_utils.get_node_at_cursor()
   local current_scope = locals.containing_scope(node_at_point, bufnr)
 
-  local start_line = current_scope:start()
+  if current_scope then
+    local start_line = current_scope:start()
 
-  if current_scope and start_line ~= 0 then
-    ts_utils.highlight_node(current_scope, bufnr, current_scope_namespace, 'TSCurrentScope')
+    if start_line ~= 0 then
+      ts_utils.highlight_node(current_scope, bufnr, current_scope_namespace, 'TSCurrentScope')
+    end
   end
 end