(* Title: Tools/quickcheck.ML
Author: Stefan Berghofer, Florian Haftmann, Lukas Bulwahn, TU Muenchen
Generic counterexample search engine.
*)
signature QUICKCHECK =
sig
val quickcheckN: string
val genuineN: string
val noneN: string
val unknownN: string
(*configuration*)
val batch_tester : string Config.T
val size : int Config.T
val iterations : int Config.T
val depth : int Config.T
val no_assms : bool Config.T
val report : bool Config.T
val timeout : real Config.T
val timing : bool Config.T
val genuine_only : bool Config.T
val abort_potential : bool Config.T
val quiet : bool Config.T
val verbose : bool Config.T
val use_subtype : bool Config.T
val allow_function_inversion : bool Config.T
val finite_types : bool Config.T
val finite_type_size : int Config.T
val tag : string Config.T
val locale : string Config.T
val set_active_testers: string list -> Context.generic -> Context.generic
datatype expectation = No_Expectation | No_Counterexample | Counterexample;
datatype test_params = Test_Params of {default_type: typ list, expect : expectation};
val test_params_of : Proof.context -> test_params
val map_test_params : (typ list * expectation -> typ list * expectation)
-> Context.generic -> Context.generic
val default_type : Proof.context -> typ list
datatype report = Report of
{ iterations : int, raised_match_errors : int,
satisfied_assms : int list, positive_concl_tests : int }
(*quickcheck's result*)
datatype result =
Result of
{counterexample : (bool * (string * term) list) option,
evaluation_terms : (term * term) list option,
timings : (string * int) list,
reports : (int * report) list}
val empty_result : result
val found_counterexample : result -> bool
val add_timing : (string * int) -> result Unsynchronized.ref -> unit
val add_response : string list -> term list -> (bool * term list) option ->
result Unsynchronized.ref -> unit
val add_report : int -> report option -> result Unsynchronized.ref -> unit
val counterexample_of : result -> (bool * (string * term) list) option
val timings_of : result -> (string * int) list
(*registering testers & generators*)
type tester =
Proof.context -> bool -> (string * typ) list -> (term * term list) list -> result list
val add_tester : string * (bool Config.T * tester) -> Context.generic -> Context.generic
val add_batch_generator :
string * (Proof.context -> term list -> (int -> term list option) list)
-> Context.generic -> Context.generic
val add_batch_validator :
string * (Proof.context -> term list -> (int -> bool) list)
-> Context.generic -> Context.generic
(*basic operations*)
val message : Proof.context -> string -> unit
val verbose_message : Proof.context -> string -> unit
val limit : Time.time -> (bool * bool) -> (unit -> 'a) -> (unit -> 'a) -> unit -> 'a
val pretty_counterex : Proof.context -> bool ->
((bool * (string * term) list) * (term * term) list) option -> Pretty.T
(*testing terms and proof states*)
val mk_batch_validator : Proof.context -> term list -> (int -> bool) list option
val mk_batch_tester : Proof.context -> term list -> (int -> term list option) list option
val active_testers : Proof.context -> tester list
val test_terms : Proof.context -> bool * bool -> (string * typ) list ->
(term * term list) list -> result list option
val quickcheck: (string * string list) list -> int -> Proof.state ->
(bool * (string * term) list) option
end;
structure Quickcheck : QUICKCHECK =
struct
val quickcheckN = "quickcheck";
val genuineN = "genuine";
val noneN = "none";
val unknownN = "unknown";
(* quickcheck report *)
datatype report = Report of
{iterations : int,
raised_match_errors : int,
satisfied_assms : int list,
positive_concl_tests : int};
(* Quickcheck Result *)
datatype result = Result of
{counterexample : (bool * (string * term) list) option,
evaluation_terms : (term * term) list option,
timings : (string * int) list,
reports : (int * report) list};
val empty_result =
Result {counterexample = NONE, evaluation_terms = NONE, timings = [], reports = []};
fun counterexample_of (Result r) = #counterexample r;
fun found_counterexample (Result r) = is_some (#counterexample r);
fun response_of (Result r) =
(case (#counterexample r, #evaluation_terms r) of
(SOME ts, SOME evals) => SOME (ts, evals)
| (NONE, NONE) => NONE);
fun timings_of (Result r) = #timings r;
fun set_response names eval_terms (SOME (genuine, ts)) (Result r) =
let
val (ts1, ts2) = chop (length names) ts
val (eval_terms', _) = chop (length ts2) eval_terms
in
Result {counterexample = SOME (genuine, (names ~~ ts1)),
evaluation_terms = SOME (eval_terms' ~~ ts2),
timings = #timings r, reports = #reports r}
end
| set_response _ _ NONE result = result;
fun cons_timing timing (Result r) =
Result {counterexample = #counterexample r, evaluation_terms = #evaluation_terms r,
timings = cons timing (#timings r), reports = #reports r};
fun cons_report size (SOME report) (Result r) =
Result {counterexample = #counterexample r, evaluation_terms = #evaluation_terms r,
timings = #timings r, reports = cons (size, report) (#reports r)}
| cons_report _ NONE result = result;
fun add_timing timing result_ref =
Unsynchronized.change result_ref (cons_timing timing);
fun add_report size report result_ref =
Unsynchronized.change result_ref (cons_report size report);
fun add_response names eval_terms response result_ref =
Unsynchronized.change result_ref (set_response names eval_terms response);
(* expectation *)
datatype expectation = No_Expectation | No_Counterexample | Counterexample;
fun merge_expectation (expect1, expect2) =
if expect1 = expect2 then expect1 else No_Expectation;
(*quickcheck configuration -- default parameters, test generators*)
val batch_tester = Attrib.setup_config_string @{binding quickcheck_batch_tester} (K "");
val size = Attrib.setup_config_int @{binding quickcheck_size} (K 10);
val iterations = Attrib.setup_config_int @{binding quickcheck_iterations} (K 100);
val depth = Attrib.setup_config_int @{binding quickcheck_depth} (K 10);
val no_assms = Attrib.setup_config_bool @{binding quickcheck_no_assms} (K false);
val locale = Attrib.setup_config_string @{binding quickcheck_locale} (K "interpret expand");
val report = Attrib.setup_config_bool @{binding quickcheck_report} (K true);
val timing = Attrib.setup_config_bool @{binding quickcheck_timing} (K false);
val timeout = Attrib.setup_config_real @{binding quickcheck_timeout} (K 30.0);
val genuine_only = Attrib.setup_config_bool @{binding quickcheck_genuine_only} (K false);
val abort_potential = Attrib.setup_config_bool @{binding quickcheck_abort_potential} (K false);
val quiet = Attrib.setup_config_bool @{binding quickcheck_quiet} (K false);
val verbose = Attrib.setup_config_bool @{binding quickcheck_verbose} (K false);
val tag = Attrib.setup_config_string @{binding quickcheck_tag} (K "");
val use_subtype = Attrib.setup_config_bool @{binding quickcheck_use_subtype} (K false);
val allow_function_inversion =
Attrib.setup_config_bool @{binding quickcheck_allow_function_inversion} (K false);
val finite_types = Attrib.setup_config_bool @{binding quickcheck_finite_types} (K true);
val finite_type_size = Attrib.setup_config_int @{binding quickcheck_finite_type_size} (K 3);
datatype test_params = Test_Params of
{default_type: typ list, expect : expectation};
fun dest_test_params (Test_Params {default_type, expect}) = (default_type, expect);
fun make_test_params (default_type, expect) =
Test_Params {default_type = default_type, expect = expect};
fun map_test_params' f (Test_Params {default_type, expect}) =
make_test_params (f (default_type, expect));
fun merge_test_params
(Test_Params {default_type = default_type1, expect = expect1},
Test_Params {default_type = default_type2, expect = expect2}) =
make_test_params
(merge (op =) (default_type1, default_type2), merge_expectation (expect1, expect2));
type tester =
Proof.context -> bool -> (string * typ) list -> (term * term list) list -> result list;
structure Data = Generic_Data
(
type T =
(string * (bool Config.T * tester)) list *
(string * (Proof.context -> term list -> (int -> term list option) list)) list *
(string * (Proof.context -> term list -> (int -> bool) list)) list *
test_params;
val empty = ([], [], [], Test_Params {default_type = [], expect = No_Expectation});
val extend = I;
fun merge
((testers1, batch_generators1, batch_validators1, params1),
(testers2, batch_generators2, batch_validators2, params2)) : T =
(AList.merge (op =) (K true) (testers1, testers2),
AList.merge (op =) (K true) (batch_generators1, batch_generators2),
AList.merge (op =) (K true) (batch_validators1, batch_validators2),
merge_test_params (params1, params2));
);
val test_params_of = #4 o Data.get o Context.Proof;
val default_type = fst o dest_test_params o test_params_of;
val expect = snd o dest_test_params o test_params_of;
val map_test_params = Data.map o @{apply 4(4)} o map_test_params';
val add_tester = Data.map o @{apply 4(1)} o AList.update (op =);
val add_batch_generator = Data.map o @{apply 4(2)} o AList.update (op =);
val add_batch_validator = Data.map o @{apply 4(3)} o AList.update (op =);
fun active_testers ctxt =
let
val testers = map snd (#1 (Data.get (Context.Proof ctxt)));
in
map snd (filter (fn (active, _) => Config.get ctxt active) testers)
end;
fun set_active_testers [] context = context
| set_active_testers testers context =
let
val registered_testers = #1 (Data.get context);
in
fold (fn (name, (config, _)) => Config.put_generic config (member (op =) testers name))
registered_testers context
end;
(* generating tests *)
fun gen_mk_tester lookup ctxt v =
let
val name = Config.get ctxt batch_tester
val tester =
(case lookup ctxt name of
NONE => error ("No such quickcheck batch-tester: " ^ name)
| SOME tester => tester ctxt);
in
if Config.get ctxt quiet then
try tester v
else
let (* FIXME !?!? *)
val tester = Exn.interruptible_capture tester v
in
(case Exn.get_res tester of
NONE => SOME (Exn.release tester)
| SOME tester => SOME tester)
end
end;
val mk_batch_tester = gen_mk_tester (AList.lookup (op =) o #2 o Data.get o Context.Proof);
val mk_batch_validator = gen_mk_tester (AList.lookup (op =) o #3 o Data.get o Context.Proof);
(* testing propositions *)
type compile_generator =
Proof.context -> (term * term list) list -> int list -> term list option * report option;
fun limit timeout (limit_time, is_interactive) f exc () =
if limit_time then
Timeout.apply timeout f ()
handle timeout_exn as Timeout.TIMEOUT _ =>
if is_interactive then exc () else Exn.reraise timeout_exn
else f ();
fun message ctxt s = if Config.get ctxt quiet then () else writeln s;
fun verbose_message ctxt s =
if not (Config.get ctxt quiet) andalso Config.get ctxt verbose
then writeln s else ();
fun test_terms ctxt (limit_time, is_interactive) insts goals =
(case active_testers ctxt of
[] => error "No active testers for quickcheck"
| testers =>
limit (seconds (Config.get ctxt timeout)) (limit_time, is_interactive)
(fn () =>
Par_List.get_some (fn tester =>
tester ctxt (length testers > 1) insts goals |>
(fn result => if exists found_counterexample result then SOME result else NONE))
testers)
(fn () => (message ctxt "Quickcheck ran out of time"; NONE)) ());
fun all_axioms_of ctxt t =
let
val intros = Locale.get_intros ctxt;
val unfolds = Locale.get_unfolds ctxt;
fun retrieve_prems thms t =
(case filter (fn th => Term.could_unify (Thm.concl_of th, t)) thms of
[] => NONE
| [th] =>
let
val (tyenv, tenv) =
Pattern.match (Proof_Context.theory_of ctxt)
(Thm.concl_of th, t) (Vartab.empty, Vartab.empty)
in SOME (map (Envir.subst_term (tyenv, tenv)) (Thm.prems_of th)) end);
fun all t =
(case retrieve_prems intros t of
NONE => retrieve_prems unfolds t
| SOME ts => SOME (maps (fn t => the_default [t] (all t)) ts));
in
all t
end;
fun locale_config_of s =
let
val cs = space_explode " " s;
in
if forall (fn c => c = "expand" orelse c = "interpret") cs then cs
else
(warning ("Invalid quickcheck_locale setting: falling back to the default setting.");
["interpret", "expand"])
end;
fun test_goal (time_limit, is_interactive) (insts, eval_terms) i state =
let
val lthy = Proof.context_of state;
val thy = Proof.theory_of state;
fun strip (Const (@{const_name Pure.all}, _) $ Abs (_, _, t)) = strip t
| strip t = t;
val {goal = st, ...} = Proof.raw_goal state;
val (gi, frees) = Logic.goal_params (Thm.prop_of st) i;
val some_locale = Named_Target.bottom_locale_of lthy;
val assms =
if Config.get lthy no_assms then []
else
(case some_locale of
NONE => Assumption.all_assms_of lthy
| SOME locale => Assumption.local_assms_of lthy (Locale.init locale thy));
val proto_goal = Logic.list_implies (map Thm.term_of assms, subst_bounds (frees, strip gi));
fun axioms_of locale =
(case fst (Locale.specification_of thy locale) of
NONE => []
| SOME t => the_default [] (all_axioms_of lthy t));
val config = locale_config_of (Config.get lthy locale);
val goals =
(case some_locale of
NONE => [(proto_goal, eval_terms)]
| SOME locale =>
fold (fn c =>
if c = "expand" then
cons (Logic.list_implies (axioms_of locale, proto_goal), eval_terms)
else if c = "interpret" then
append (map (fn (_, phi) =>
(Morphism.term phi proto_goal, map (Morphism.term phi) eval_terms))
(Locale.registrations_of (Context.Theory thy) (* FIXME !? *) locale))
else I) config []);
val _ =
verbose_message lthy
(Pretty.string_of
(Pretty.big_list ("Checking goals: ") (map (Syntax.pretty_term lthy o fst) goals)));
in
test_terms lthy (time_limit, is_interactive) insts goals
end;
(* pretty printing *)
fun tool_name auto = if auto then "Auto Quickcheck" else "Quickcheck";
fun pretty_counterex ctxt auto NONE =
Pretty.para (tool_name auto ^ " found no counterexample." ^ Config.get ctxt tag)
| pretty_counterex ctxt auto (SOME ((genuine, cex), eval_terms)) =
let
val header =
Pretty.para
(tool_name auto ^ " found a " ^
(if genuine then "counterexample"
else "potentially spurious counterexample due to underspecified functions") ^
(if null cex then "." else ":") ^
Config.get ctxt tag);
fun pretty_cex (x, t) =
Pretty.block [Pretty.str (x ^ " ="), Pretty.brk 1, Syntax.pretty_term ctxt t];
in
Pretty.chunks (Pretty.block (Pretty.fbreaks (header :: map pretty_cex (rev cex))) ::
(if null eval_terms then []
else
[Pretty.big_list "Evaluated terms:"
(map (fn (t, u) =>
Pretty.block [Syntax.pretty_term ctxt t, Pretty.str " =", Pretty.brk 1,
Syntax.pretty_term ctxt u]) (rev eval_terms))]))
end;
(* Isar commands *)
fun read_nat s =
(case Library.read_int (Symbol.explode s) of
(k, []) =>
if k >= 0 then k
else error ("Not a natural number: " ^ s)
| _ => error ("Not a natural number: " ^ s));
fun read_bool "false" = false
| read_bool "true" = true
| read_bool s = error ("Not a Boolean value: " ^ s);
fun read_real s =
(case Real.fromString s of
SOME s => s
| NONE => error ("Not a real number: " ^ s));
fun read_expectation "no_expectation" = No_Expectation
| read_expectation "no_counterexample" = No_Counterexample
| read_expectation "counterexample" = Counterexample
| read_expectation s = error ("Not an expectation value: " ^ s);
fun valid_tester_name context name =
AList.defined (op =) (#1 (Data.get context)) name;
fun parse_tester name (testers, context) =
if valid_tester_name context name then
(insert (op =) name testers, context)
else error ("Unknown tester: " ^ name);
fun parse_test_param ("tester", args) = fold parse_tester args
| parse_test_param ("size", [arg]) = apsnd (Config.put_generic size (read_nat arg))
| parse_test_param ("iterations", [arg]) = apsnd (Config.put_generic iterations (read_nat arg))
| parse_test_param ("depth", [arg]) = apsnd (Config.put_generic depth (read_nat arg))
| parse_test_param ("default_type", arg) =
(fn (testers, context) =>
(testers, map_test_params
(apfst (K (map (Proof_Context.read_typ (Context.proof_of context)) arg))) context))
| parse_test_param ("no_assms", [arg]) = apsnd (Config.put_generic no_assms (read_bool arg))
| parse_test_param ("expect", [arg]) = apsnd (map_test_params (apsnd (K (read_expectation arg))))
| parse_test_param ("report", [arg]) = apsnd (Config.put_generic report (read_bool arg))
| parse_test_param ("genuine_only", [arg]) =
apsnd (Config.put_generic genuine_only (read_bool arg))
| parse_test_param ("abort_potential", [arg]) =
apsnd (Config.put_generic abort_potential (read_bool arg))
| parse_test_param ("quiet", [arg]) = apsnd (Config.put_generic quiet (read_bool arg))
| parse_test_param ("verbose", [arg]) = apsnd (Config.put_generic verbose (read_bool arg))
| parse_test_param ("tag", [arg]) = apsnd (Config.put_generic tag arg)
| parse_test_param ("use_subtype", [arg]) =
apsnd (Config.put_generic use_subtype (read_bool arg))
| parse_test_param ("timeout", [arg]) =
apsnd (Config.put_generic timeout (read_real arg))
| parse_test_param ("finite_types", [arg]) =
apsnd (Config.put_generic finite_types (read_bool arg))
| parse_test_param ("allow_function_inversion", [arg]) =
apsnd (Config.put_generic allow_function_inversion (read_bool arg))
| parse_test_param ("finite_type_size", [arg]) =
apsnd (Config.put_generic finite_type_size (read_nat arg))
| parse_test_param (name, _) =
(fn (testers, context) =>
if valid_tester_name context name then
(insert (op =) name testers, context)
else error ("Unknown tester or test parameter: " ^ name));
fun parse_test_param_inst (name, arg) ((insts, eval_terms), (testers, ctxt)) =
(case try (Proof_Context.read_typ ctxt) name of
SOME (TFree (v, _)) =>
((AList.update (op =) (v, Proof_Context.read_typ ctxt (the_single arg)) insts, eval_terms),
(testers, ctxt))
| NONE =>
(case name of
"eval" => ((insts, eval_terms @ map (Syntax.read_term ctxt) arg), (testers, ctxt))
| _ =>
((insts, eval_terms),
let
val (testers', Context.Proof ctxt') =
parse_test_param (name, arg) (testers, Context.Proof ctxt);
in (testers', ctxt') end)));
fun quickcheck_params_cmd args =
Context.theory_map
(fn context => uncurry set_active_testers (fold parse_test_param args ([], context)));
fun check_expectation state results =
if is_some results andalso expect (Proof.context_of state) = No_Counterexample then
error "quickcheck expected to find no counterexample but found one"
else if is_none results andalso expect (Proof.context_of state) = Counterexample then
error "quickcheck expected to find a counterexample but did not find one"
else ();
fun gen_quickcheck args i state =
state
|> Proof.map_context_result (fn ctxt =>
apsnd (fn (testers, ctxt) => Context.proof_map (set_active_testers testers) ctxt)
(fold parse_test_param_inst args (([], []), ([], ctxt))))
|> (fn ((insts, eval_terms), state') =>
test_goal (true, true) (insts, eval_terms) i state'
|> tap (check_expectation state')
|> rpair state');
fun quickcheck args i state =
Option.map (the o get_first counterexample_of) (fst (gen_quickcheck args i state));
fun quickcheck_cmd args i st =
gen_quickcheck args i (Toplevel.proof_of st)
|> apfst (Option.map (the o get_first response_of))
|> (fn (r, state) =>
writeln (Pretty.string_of
(pretty_counterex (Proof.context_of state) false r)));
val parse_arg =
Parse.name --
(Scan.optional (@{keyword "="} |--
(((Parse.name || Parse.float_number) >> single) ||
(@{keyword "["} |-- Parse.list1 Parse.name --| @{keyword "]"}))) ["true"]);
val parse_args =
@{keyword "["} |-- Parse.list1 parse_arg --| @{keyword "]"} || Scan.succeed [];
val _ =
Outer_Syntax.command @{command_keyword quickcheck_params} "set parameters for random testing"
(parse_args >> (fn args => Toplevel.theory (quickcheck_params_cmd args)));
val _ =
Outer_Syntax.command @{command_keyword quickcheck}
"try to find counterexample for subgoal"
(parse_args -- Scan.optional Parse.nat 1 >>
(fn (args, i) => Toplevel.keep_proof (quickcheck_cmd args i)));
(* automatic testing *)
fun try_quickcheck auto state =
let
val ctxt = Proof.context_of state;
val i = 1;
val res =
state
|> Proof.map_context (Config.put report false #> Config.put quiet true)
|> try (test_goal (false, false) ([], []) i);
in
(case res of
NONE => (unknownN, [])
| SOME results =>
let
val msg =
Pretty.string_of
(pretty_counterex ctxt auto (Option.map (the o get_first response_of) results))
in
if is_some results then (genuineN, if auto then [msg] else (writeln msg; []))
else (noneN, [])
end)
end
|> `(fn (outcome_code, _) => outcome_code = genuineN);
val _ = Try.tool_setup (quickcheckN, (20, @{system_option auto_quickcheck}, try_quickcheck));
end;