model so far

improved model

quickcheck/aeb_fate_code_tests.erl

@@ -21,5 +21,7 @@
 quickcheck_test_() ->
     {setup, fun() -> eqc:start() end,
      [ ?EQC_EUNIT(aefate_code_eqc, prop_opcodes, 200),
-       ?EQC_EUNIT(aefate_code_eqc, prop_serializes, 3000)
+       ?EQC_EUNIT(aefate_code_eqc, prop_serializes, 3000),
+       ?EQC_EUNIT(aefate_code_eqc, prop_fail_serializes, 3000),
+       ?EQC_EUNIT(aefate_code_eqc, prop_fuzz, 3000)
      ]}.

quickcheck/aefate_code_eqc.erl

@@ -6,6 +6,13 @@
 %%% We test something slightly weaker here,
 %%%    viz. All FATE assembler we serialize, we can deserialize
 %%%
+%%%    Negative testing modelled:
+%%%       Failure 1: function names differ from 4 bytes
+%%%       Failure 2: pointer to empty code block
+%%%       Failure 3: end_BB operation as not ending block or not at end of block
+%%%       - empty code blocks
+%%%       - blocks that are not of the form (not end_bb)* end_bb.
+%%%
 %%% @end
 %%% Created : 13 Dec 2018 by Thomas Arts <thomas@SpaceGrey.lan>
 
@@ -14,21 +21,41 @@
 -include_lib("eqc/include/eqc.hrl").
 
 -compile([export_all, nowarn_export_all]).
+%%-define(Failure(Failures, Number), case lists:member(Number, Failures) of true -> 1; false -> 0 end)
+
 
 prop_serializes() ->
     in_parallel(
-    ?FORALL(FateCode, fate_code(),
+    ?FORALL(FateCode, fate_code(0),
            ?WHENFAIL(eqc:format("Trying to serialize/deserialize ~p failed~n", [FateCode]),
                       begin
-                          {T1, Binary} =
+                          Binary = aeb_fate_code:serialize(FateCode),
-                              timer:tc( fun() -> aeb_fate_code:serialize(FateCode) end),
+                          ?WHENFAIL(eqc:format("serialized: ~p~n", [Binary]),
-                          {T2, Decoded} =
+                                    begin
-                              timer:tc(fun() -> aeb_fate_code:deserialize(Binary) end),
+                                        Decoded = aeb_fate_code:deserialize(Binary),
                                         measure(binary_size, size(Binary),
-                          measure(encode, T1,
+                                                equals(Decoded, FateCode))
-                          measure(decode, T2,
+                                    end)
-                                  conjunction([{equal, equals(Decoded, FateCode)},
+                      end))).
-                                              {decoding_time, true}]))))
+
+prop_fail_serializes() ->
+    conjunction([{Failure, eqc:counterexample(
+                             ?FORALL(FateCode, fate_code(Failure),
+                               ?FORALL(Binary, catch aeb_fate_code:serialize(FateCode),
+                                         is_binary(aeb_fate_code:serialize(FateCode)))))
+                             =/= true} || Failure <- [1,2,3,4] ]).
+
+prop_fuzz() ->
+    in_parallel(
+    ?FORALL(Binary, ?LET(FateCode, fate_code(0), aeb_fate_code:serialize(FateCode)),
+            ?FORALL(InjectedBin, injection(Binary),
+                    try Org = aeb_fate_code:deserialize(InjectedBin),
+                         NewBin = aeb_fate_code:serialize(Org),
+                         NewOrg = aeb_fate_code:deserialize(NewBin),
+                         ?WHENFAIL(eqc:format("Deserialize ~p gives\n~p\nSerializes to ~p\n", [InjectedBin, Org, NewOrg]),
+                                   equals(NewBin, InjectedBin))
+                    catch _:_ ->
+                            true
                     end))).
 
 prop_opcodes() ->
@@ -44,13 +71,15 @@ prop_opcodes() ->
 
 
 valid_opcodes() ->
-    lists:seq(0, 16#72) ++ lists:seq(16#fa, 16#ff).
+    lists:seq(0, 16#72) ++ lists:seq(16#fa, 16#fd).
 
 
-fate_code() ->
+fate_code(Failure) ->
     ?SIZED(Size,
            ?LET({FMap, SMap, AMap},
-                {map(binary(4), {{list(aefate_type_eqc:fate_type(Size div 3)), aefate_type_eqc:fate_type(Size div 3)}, bb_code()}),
+                {non_empty(map(if Failure == 1 -> binary(1);
+                        true -> binary(4) end,
+                     {{list(aefate_type_eqc:fate_type(Size div 3)), aefate_type_eqc:fate_type(Size div 3)}, bbs_code(Failure)})),
                  map(resize(Size div 5, aefate_eqc:fate_data()), resize(Size div 3, aefate_eqc:fate_data())),
                  map(resize(Size div 5, aefate_eqc:fate_data()), resize(Size div 4, aefate_eqc:fate_data()))},
                 aeb_fate_code:update_annotations(
@@ -58,5 +87,43 @@ fate_code() ->
                     aeb_fate_code:update_functions(
                       aeb_fate_code:new(), FMap), SMap), AMap))).
 
-bb_code() ->
+bbs_code(Failure) ->
-    #{}.
+    frequency([{if Failure == 2 -> 5; true -> 0 end, #{0 => []}},
+               {10, ?LET(BBs, list(bb_code(Failure)),
+                          maps:from_list(
+                            lists:zip(lists:seq(0, length(BBs)-1), BBs)))}]).
+
+bb_code(Failure) ->
+    EndBB = [ Op || Op <- valid_opcodes(), aeb_fate_opcodes:end_bb(Op) ],
+    NonEndBB = valid_opcodes() -- EndBB,
+    frequency(
+      [{if Failure == 3 -> 5; true -> 0 end, ?LET(Ops, non_empty(list(elements(valid_opcodes()))), bblock(Failure, Ops))},
+       {10, ?LET({Ops, Op}, {list(elements(NonEndBB)), elements(EndBB)},
+                  bblock(Failure, Ops ++ [Op]))}]).
+
+bblock(Failure, Ops) ->
+    [ begin
+          Mnemonic = aeb_fate_opcodes:mnemonic(Op),
+          Arity = aeb_fate_opcodes:args(Op),
+          case Arity of
+              0 -> Mnemonic;
+              _ -> list_to_tuple([Mnemonic |
+                                  [ frequency([{if Failure == 4 -> 5; true -> 0 end, {stack, nat()}},
+                                               {5, {stack, 0}},
+                                               {5, {arg, nat()}},
+                                               {5, {var, nat()}},
+                                               {5, {immediate, small_fate_data(4)}}]) ||
+                                      _ <- lists:seq(1, Arity) ]])
+          end
+      end || Op <- Ops ].
+
+injection(Binary) ->
+    ?LET({N, Inj}, {choose(0, byte_size(Binary) - 1), choose(0,255)},
+         begin
+             M = N * 8,
+             <<X:M, _:8, Z/binary>> = Binary,
+             <<X:M, Inj:8, Z/binary>>
+         end).
+
+small_fate_data(N) ->
+    ?SIZED(Size, resize(Size div N, aefate_eqc:fate_data())).