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%%---------------------------------------------------------------------------
%% From: Jeff Hlywa
%% Subject: Increasing max_size significantly degrades performance.
%%---------------------------------------------------------------------------
%% Using the code below I get:
%% 1> timer:tc(fun() ->
%% proper:quickcheck(perf_max_size:prop_identity(), [5, {max_size, 42}])
%% end).
%% .....
%% OK: Passed 5 test(s).
%% {8170,true}
%%
%% 2> timer:tc(fun() ->
%% proper:quickcheck(perf_max_size:prop_identity(),
%% [5, {max_size, 16#ffffffff}])
%% end).
%% ....
%% OK: Passed 5 test(s).
%% {658751072,true}
%%
%% Not able to determine the cause of the slowdown, but it's significant.
%% ---------------------------------------------------------------------------
%% Fixed on 29/3/2013. The fix was that when increasing the size, move
%% to the next value immediately instead of trying each value one-by-one.
%% ---------------------------------------------------------------------------
-module(perf_max_size).
-export([prop_identity/0]).
-include_lib("proper/include/proper.hrl").
-record(msg, {a = 0 :: 0..16#ffffffff, b = 0 :: 0..16#f}).
-type msg() :: #msg{}.
prop_identity() ->
?FORALL(Msg, msg(), Msg =:= decode(encode(Msg))).
-spec encode(msg()) -> bitstring().
encode(#msg{a = A, b = B}) ->
<<A:32, B:4>>.
-spec decode(bitstring()) -> msg().
decode(<<A:32, B:4>>) ->
#msg{a = A, b = B}.
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