Resistance and support lines are drawn based on the iFractals indicator. The indicator takes into account the fact that the last value of Fractals can be redrawn, therefore +5 additional bars are analyzed:

//--- number of values copied from the iFractals indicator 
   int values_to_copy=-1;
//--- if it is the first start of calculation of the indicator
   if(prev_calculated==0)
      values_to_copy=rates_total;
   else
     {
      //--- it means that it's not the first time of the indicator calculation, and since the last call of OnCalculate() 
      //--- for calculation not more than one bar is added 
      //--- value "+5" - because of the feature of drawing fractals
      values_to_copy=(rates_total-prev_calculated)+5;
     }

In order to compare "Resistance & Support" and "Fractals" in the strategy tester, do the following:

• Attach "Fractals" on a clear chart.
• Then right-click on the chart → Templates → Save Template. Use "tester" for the name of the template. As a result, you save the chart with the attached Fractals indicator in the "tester.tpl" template.
• Start:
  • Either debugging on history (from the MetaEditor by pressing "Ctrl" + "F5")
  • Or visual testing (from the terminal, from the Strategy Tester window).

Testing of the "Resistance & Support" indicator in the strategy tester is shown below: