6.84 find number of points used in Plot command?

see how-to-return-the-value-of-automatic-when-it-is-used-in-a-mathematica-function

Thanks to Bob Hanlon for this method:

p1 = Plot[Sin[x], {x, 0, Pi}, PlotPoints -> Automatic] 
Cases[p1, Line[pts_] :> Length[pts], Infinity] 
  (*259*)
 

Another method due to Simon Woods

Trace[ 
 Plot[Sin[t], {t, 0, 2 Pi}], 
 HoldPattern[PlotPoints | MaxRecursion -> _], 
 TraceInternal -> True] // Flatten // Union 
 
  {MaxRecursion -> 6, MaxRecursion -> Automatic, PlotPoints -> 50, 
     PlotPoints -> Automatic}