From 75f3eeffa7b06f406eb992266833b623e1664850 Mon Sep 17 00:00:00 2001
From: Thomas Arts <thomas.arts@robuster.software>
Date: Tue, 9 Apr 2019 10:32:08 +0200
Subject: [PATCH] Add quickcheck properties

---
 quickcheck/aefate_eqc.erl | 107 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 107 insertions(+)
 create mode 100644 quickcheck/aefate_eqc.erl

diff --git a/quickcheck/aefate_eqc.erl b/quickcheck/aefate_eqc.erl
new file mode 100644
index 0000000..3049c41
--- /dev/null
+++ b/quickcheck/aefate_eqc.erl
@@ -0,0 +1,107 @@
+%%% @author Thomas Arts
+%%% @copyright (C) 2018, Thomas Arts
+%%% @doc Use `rebar3 as eqc shell` to run properties in the shell
+%%%
+%%%
+%%% @end
+%%% Created : 13 Dec 2018 by Thomas Arts <thomas@SpaceGrey.lan>
+
+-module(aefate_eqc).
+
+-include_lib("eqc/include/eqc.hrl").
+
+-compile([export_all, nowarn_export_all]).
+
+prop_roundtrip() ->
+    ?FORALL(FateData, fate_type(),
+            measure(bytes, size(term_to_binary(FateData)),
+                    begin
+                        Serialized = aeb_fate_encoding:serialize(FateData),
+                        ?WHENFAIL(eqc:format("Serialized ~p to ~p~n", [FateData, Serialized]),
+                                  equals(aeb_fate_encoding:deserialize(Serialized), FateData))
+                    end
+                   )).
+
+prop_format() ->
+    ?FORALL(FateData, fate_type(),
+            ?WHENFAIL(eqc:format("Trying to format ~p failed~n",[FateData]),
+                      begin
+                          String = aeb_fate_data:format(FateData),
+                          collect([FateData, unicode:characters_to_binary(String, latin1)], true)
+                      end)).
+
+prop_format_scan() ->
+    ?FORALL(FateData, fate_type(),
+            ?WHENFAIL(eqc:format("Trying to format ~p failed~n~p~n", [FateData, catch unicode:characters_to_list(aeb_fate_data:format(FateData), utf8) ]),
+                      begin
+                          String = aeb_fate_data:format(FateData),
+                          {ok, _Scanned, _} = aeb_fate_asm_scan:scan(unicode:characters_to_list(String)),
+                          true
+                      end)).
+
+fate_type() ->
+    ?SIZED(Size, fate_type(Size, [map])).
+
+fate_type(0, _Options) ->
+    ?LAZY(
+       oneof([fate_integer(),
+              fate_boolean(),
+              fate_nil(),
+              fate_unit(),
+              fate_string(),
+              fate_address(),
+              fate_hash(),
+              fate_signature(),
+              fate_contract(),
+              fate_oracle(),
+              fate_name(),
+              fate_bits(),
+              fate_channel()]));
+fate_type(Size, Options) ->
+    ?LETSHRINK([Smaller], [?LAZY(fate_type(Size div 5, Options))],
+    oneof([?LAZY(fate_type(Size - 1, Options)),
+           ?LAZY(fate_list( Smaller )),
+           ?LAZY(fate_tuple( list( Smaller ))),
+           ?LAZY(fate_variant(?LET(L, list( Smaller), list_to_tuple(L))))] ++
+              [
+               ?LAZY(fate_map( fate_type(Size div 3, Options -- [map]),
+                               Smaller))
+              || lists:member(map, Options)
+              ])).
+
+
+fate_integer()    -> oneof([int(), largeint()]).
+fate_bits()       -> {bits, oneof([int(), largeint()])}.
+fate_boolean()    -> elements([true, false]).
+fate_nil()        -> [].
+fate_unit()       -> {tuple, {}}.
+fate_string()     -> ?SUCHTHAT(S, utf8(), string:find(S, "\"") == nomatch).
+fate_address()    -> {address, non_zero_binary(256 div 8)}.
+fate_hash()       -> {hash, non_zero_binary(32)}.
+fate_signature()  -> {signature, non_zero_binary(64)}.
+fate_contract()   -> {contract, non_zero_binary(256 div 8)}.
+fate_oracle()     -> {oracle, non_zero_binary(256 div 8)}.
+fate_name()       -> {name, non_zero_binary(256 div 8)}.
+fate_channel()    -> {channel, non_zero_binary(256 div 8)}.
+
+%% May shrink to fate_unit
+fate_tuple(ListGen) ->
+    {tuple, ?LET(Elements, ListGen, list_to_tuple(Elements))}.
+
+fate_variant(TupleGen) ->
+    ?LET({L1, L2, Tuple}, {list(choose(0, 255)), list(choose(0,255)), TupleGen},
+         {variant, L1 ++ [size(Tuple)] ++ L2, length(L1), Tuple}).
+
+fate_list(Gen) ->
+    oneof([fate_nil(), ?SHRINK(list(Gen), [fate_nil()])]).
+
+fate_map(KeyGen, ValGen) ->
+    map(KeyGen, ValGen).
+
+
+non_zero_binary(N) ->
+    Bits = N*8,
+    ?SUCHTHAT(Bin, binary(N), begin <<V:Bits>> = Bin, V =/= 0 end).
+
+char() ->
+    choose(1, 255).