anchor.diff:  				  throw(Err1)
        			  end,
        			  case F1==F2 of 
  -     			      true -> ok;
  +     			      true -> ok; 
        			      false ->
        				  case file:rename(F1, F2) of 
        				      ok -> ok;
  
positive.code: 
  %%-spec(abort/0::() ->{ok, [filename()]}).
  
  abort(_IsCompositeRefac) -> %% This function will be extended!
      gen_server:call(wrangler_preview_server, abort).
  abort() ->
      gen_server:call(wrangler_preview_server, abort).
     
  
negative.code: -behaviour(gen_server).
  
  %% API
  -export([commit/0, abort/0,add_files/1, start_preview_server/0]).
  
  %% gen_server callbacks
  -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
  