diff options
Diffstat (limited to 'lib/dialyzer/src/dialyzer_typesig.erl')
-rw-r--r-- | lib/dialyzer/src/dialyzer_typesig.erl | 204 |
1 files changed, 191 insertions, 13 deletions
diff --git a/lib/dialyzer/src/dialyzer_typesig.erl b/lib/dialyzer/src/dialyzer_typesig.erl index 5f0881bbcd..50fcbc555b 100644 --- a/lib/dialyzer/src/dialyzer_typesig.erl +++ b/lib/dialyzer/src/dialyzer_typesig.erl @@ -48,6 +48,7 @@ t_is_float/1, t_is_fun/1, t_is_integer/1, t_non_neg_integer/0, t_is_list/1, t_is_nil/1, t_is_none/1, t_is_number/1, + t_is_singleton/1, t_limit/2, t_list/0, t_list/1, t_list_elements/1, t_nonempty_list/1, t_maybe_improper_list/0, @@ -57,7 +58,7 @@ t_timeout/0, t_tuple/0, t_tuple/1, t_var/1, t_var_name/1, t_none/0, t_unit/0, - t_map/1 + t_map/0, t_map/1, t_map_get/2, t_map_put/2 ]). -include("dialyzer.hrl"). @@ -126,6 +127,8 @@ solvers = [] :: [solver()] }). +-type state() :: #state{}. + %%----------------------------------------------------------------------------- -define(TYPE_LIMIT, 4). @@ -311,7 +314,7 @@ traverse(Tree, DefinedVars, State) -> Hd = cerl:cons_hd(Tree), Tl = cerl:cons_tl(Tree), {State1, [HdVar, TlVar]} = traverse_list([Hd, Tl], DefinedVars, State), - case cerl:is_literal(cerl:fold_literal(Tree)) of + case cerl:is_literal(fold_literal_maybe_match(Tree, State)) of true -> %% We do not need to do anything more here. {State, t_cons(HdVar, TlVar)}; @@ -392,8 +395,18 @@ traverse(Tree, DefinedVars, State) -> {State2, _} = traverse_list(Funs, DefinedVars1, State1), traverse(Body, DefinedVars1, State2); literal -> - Type = t_from_term(cerl:concrete(Tree)), - {State, Type}; + %% Maps are special; a literal pattern matches more than just the value + %% constructed by the literal. For example #{} constructs the empty map, + %% but matches every map. + case state__is_in_match(State) of + true -> + Tree1 = dialyzer_utils:refold_pattern(Tree), + case cerl:is_literal(Tree1) of + false -> traverse(Tree1, DefinedVars, State); + true -> {State, t_from_term(cerl:concrete(Tree))} + end; + _ -> {State, t_from_term(cerl:concrete(Tree))} + end; module -> Defs = cerl:module_defs(Tree), Funs = [Fun || {_Var, Fun} <- Defs], @@ -437,7 +450,7 @@ traverse(Tree, DefinedVars, State) -> Elements = cerl:tuple_es(Tree), {State1, EVars} = traverse_list(Elements, DefinedVars, State), {State2, TupleType} = - case cerl:is_literal(cerl:fold_literal(Tree)) of + case cerl:is_literal(fold_literal_maybe_match(Tree, State1)) of true -> %% We do not need to do anything more here. {State, t_tuple(EVars)}; @@ -476,7 +489,111 @@ traverse(Tree, DefinedVars, State) -> [] -> {State2, TupleType} end; map -> - {State, t_map([])}; + Entries = cerl:map_es(Tree), + MapFoldFun = fun(Entry, AccState) -> + AccState1 = state__set_in_match(AccState, false), + {AccState2, KeyVar} = traverse(cerl:map_pair_key(Entry), + DefinedVars, AccState1), + AccState3 = state__set_in_match( + AccState2, state__is_in_match(AccState)), + {AccState4, ValVar} = traverse(cerl:map_pair_val(Entry), + DefinedVars, AccState3), + {{KeyVar, ValVar}, AccState4} + end, + {Pairs, State1} = lists:mapfoldl(MapFoldFun, State, Entries), + %% We mustn't recurse into map arguments to matches. Not only are they + %% syntactically only allowed to be the literal #{}, but that would also + %% cause an infinite recursion, since traverse/3 unfolds literals with + %% maps in them using dialyzer_utils:reflow_pattern/1. + {State2, ArgVar} = + case state__is_in_match(State) of + false -> traverse(cerl:map_arg(Tree), DefinedVars, State1); + true -> {State1, t_map()} + end, + MapVar = mk_var(Tree), + MapType = ?mk_fun_var( + fun(Map) -> + lists:foldl( + fun({K,V}, TypeAcc) -> + t_map_put({lookup_type(K, Map), + lookup_type(V, Map)}, + TypeAcc) + end, t_inf(t_map(), lookup_type(ArgVar, Map)), + Pairs) + end, [ArgVar | lists:append([[K,V] || {K,V} <- Pairs])]), + %% TODO: does the "same element appearing several times" problem apply + %% here too? + Fun = + fun({KeyVar, ValVar}, {AccState, ShadowKeys}) -> + %% If Val is known to be the last association of Key (i.e. Key + %% is not in ShadowKeys), Val must be a subtype of what is + %% associated to Key in Tree + TypeFun = + fun(Map) -> + KeyType = lookup_type(KeyVar, Map), + case t_is_singleton(KeyType) of + false -> t_any(); + true -> + MT = t_inf(lookup_type(MapVar, Map), t_map()), + case t_is_none(MT) of + true -> t_none(); + false -> + DisjointFromKeyType = + fun(ShadowKey) -> + t_is_none(t_inf(lookup_type(ShadowKey, Map), + KeyType)) + end, + case lists:all(DisjointFromKeyType, ShadowKeys) of + true -> t_map_get(KeyType, MT); + %% A later association might shadow this one + false -> t_any() + end + end + end + end, + ValType = ?mk_fun_var(TypeFun, [KeyVar, MapVar | ShadowKeys]), + {state__store_conj(ValVar, sub, ValType, AccState), + [KeyVar | ShadowKeys]} + end, + %% Accumulate shadowing keys right-to-left + {State3, _} = lists:foldr(Fun, {State2, []}, Pairs), + %% In a map expression, Arg must contain all keys that are inserted with + %% the exact (:=) operator, and are known (i.e. are not in ShadowedKeys) + %% to not have been introduced by a previous association + State4 = + case state__is_in_match(State) of + true -> State3; + false -> + ArgFun = + fun(Map) -> + FoldFun = + fun({{KeyVar, _}, Entry}, {AccType, ShadowedKeys}) -> + OpTree = cerl:map_pair_op(Entry), + KeyType = lookup_type(KeyVar, Map), + AccType1 = + case cerl:is_literal(OpTree) andalso + cerl:concrete(OpTree) =:= exact of + true -> + case t_is_none(t_inf(ShadowedKeys, KeyType)) of + true -> + t_map_put({KeyType, t_any()}, AccType); + false -> + AccType + end; + false -> + AccType + end, + {AccType1, t_sup(KeyType, ShadowedKeys)} + end, + %% Accumulate shadowed keys left-to-right + {ResType, _} = lists:foldl(FoldFun, {t_map(), t_none()}, + lists:zip(Pairs, Entries)), + ResType + end, + ArgType = ?mk_fun_var(ArgFun, [KeyVar || {KeyVar, _} <- Pairs]), + state__store_conj(ArgVar, sub, ArgType, State3) + end, + {state__store_conj(MapVar, sub, MapType, State4), MapVar}; values -> %% We can get into trouble when unifying products that have the %% same element appearing several times. Handle these cases by @@ -948,6 +1065,7 @@ get_type_test({erlang, is_float, 1}) -> {ok, t_float()}; get_type_test({erlang, is_function, 1}) -> {ok, t_fun()}; get_type_test({erlang, is_integer, 1}) -> {ok, t_integer()}; get_type_test({erlang, is_list, 1}) -> {ok, t_list()}; +get_type_test({erlang, is_map, 1}) -> {ok, t_map()}; get_type_test({erlang, is_number, 1}) -> {ok, t_number()}; get_type_test({erlang, is_pid, 1}) -> {ok, t_pid()}; get_type_test({erlang, is_port, 1}) -> {ok, t_port()}; @@ -1004,7 +1122,9 @@ bitstr_val_constr(SizeType, UnitVal, Flags) -> end end. -get_safe_underapprox_1([Pat|Left], Acc, Map) -> +get_safe_underapprox_1([Pat0|Left], Acc, Map) -> + %% Maps should be treated as patterns, not as literals + Pat = dialyzer_utils:refold_pattern(Pat0), case cerl:type(Pat) of alias -> APat = cerl:alias_pat(Pat), @@ -1048,8 +1168,35 @@ get_safe_underapprox_1([Pat|Left], Acc, Map) -> Type = t_tuple(Ts), get_safe_underapprox_1(Left, [Type|Acc], Map1); map -> - %% TODO: Can maybe do something here - throw(dont_know); + %% Some assertions in case the syntax gets more premissive in the future + true = #{} =:= cerl:concrete(cerl:map_arg(Pat)), + true = lists:all(fun(P) -> + cerl:is_literal(Op = cerl:map_pair_op(P)) andalso + exact =:= cerl:concrete(Op) + end, cerl:map_es(Pat)), + KeyTrees = lists:map(fun cerl:map_pair_key/1, cerl:map_es(Pat)), + ValTrees = lists:map(fun cerl:map_pair_val/1, cerl:map_es(Pat)), + %% Keys must not be underapproximated. Overapproximations are safe. + Keys = get_safe_overapprox(KeyTrees), + {Vals, Map1} = get_safe_underapprox_1(ValTrees, [], Map), + case lists:all(fun erl_types:t_is_singleton/1, Keys) of + false -> throw(dont_know); + true -> ok + end, + SortedPairs = lists:sort(lists:zip(Keys, Vals)), + %% We need to deal with duplicates ourselves + SquashDuplicates = + fun SquashDuplicates([{K,First},{K,Second}|List]) -> + case t_is_none(Inf = t_inf(First, Second)) of + true -> throw(dont_know); + false -> [{K, Inf}|SquashDuplicates(List)] + end; + SquashDuplicates([Good|Rest]) -> + [Good|SquashDuplicates(Rest)]; + SquashDuplicates([]) -> [] + end, + Type = t_map(SquashDuplicates(SortedPairs)), + get_safe_underapprox_1(Left, [Type|Acc], Map1); values -> Es = cerl:values_es(Pat), {Ts, Map1} = get_safe_underapprox_1(Es, [], Map), @@ -1064,6 +1211,15 @@ get_safe_underapprox_1([Pat|Left], Acc, Map) -> get_safe_underapprox_1([], Acc, Map) -> {lists:reverse(Acc), Map}. +get_safe_overapprox(Pats) -> + lists:map(fun get_safe_overapprox_1/1, Pats). + +get_safe_overapprox_1(Pat) -> + case cerl:is_literal(Lit = cerl:fold_literal(Pat)) of + true -> t_from_term(cerl:concrete(Lit)); + false -> t_any() + end. + %%---------------------------------------- %% Guards %% @@ -1263,6 +1419,8 @@ get_bif_constr({erlang, is_integer, 1}, Dst, [Arg], State) -> get_bif_test_constr(Dst, Arg, t_integer(), State); get_bif_constr({erlang, is_list, 1}, Dst, [Arg], State) -> get_bif_test_constr(Dst, Arg, t_maybe_improper_list(), State); +get_bif_constr({erlang, is_map, 1}, Dst, [Arg], State) -> + get_bif_test_constr(Dst, Arg, t_map(), State); get_bif_constr({erlang, is_number, 1}, Dst, [Arg], State) -> get_bif_test_constr(Dst, Arg, t_number(), State); get_bif_constr({erlang, is_pid, 1}, Dst, [Arg], State) -> @@ -1900,7 +2058,7 @@ sane_maps(Map1, Map2, Keys, _S1, _S2) -> %% Solver v2 -record(v2_state, {constr_data = dict:new() :: dict:dict(), - state :: #state{}}). + state :: state()}). v2_solve_ref(Fun, Map, State) -> V2State = #v2_state{state = State}, @@ -2975,13 +3133,24 @@ mk_constraint_ref(Id, Deps) -> mk_constraint_list(Type, List) -> List1 = ordsets:from_list(lift_lists(Type, List)), - List2 = ordsets:filter(fun(X) -> get_deps(X) =/= [] end, List1), - Deps = calculate_deps(List2), + case Type of + conj -> + List2 = ordsets:filter(fun(X) -> get_deps(X) =/= [] end, List1), + mk_constraint_list_cont(Type, List2); + disj -> + case lists:any(fun(X) -> get_deps(X) =:= [] end, List1) of + true -> mk_constraint_list_cont(Type, [mk_constraint_any(eq)]); + false -> mk_constraint_list_cont(Type, List1) + end + end. + +mk_constraint_list_cont(Type, List) -> + Deps = calculate_deps(List), case Deps =:= [] of true -> #constraint_list{type = conj, list = [mk_constraint_any(eq)], deps = []}; - false -> #constraint_list{type = Type, list = List2, deps = Deps} + false -> #constraint_list{type = Type, list = List, deps = Deps} end. lift_lists(Type, List) -> @@ -3263,6 +3432,15 @@ find_constraint(Tuple, [#constraint_list{list = List}|Cs]) -> find_constraint(Tuple, [_|Cs]) -> find_constraint(Tuple, Cs). +-spec fold_literal_maybe_match(cerl:cerl(), state()) -> cerl:cerl(). + +fold_literal_maybe_match(Tree0, State) -> + Tree1 = cerl:fold_literal(Tree0), + case state__is_in_match(State) of + false -> Tree1; + true -> dialyzer_utils:refold_pattern(Tree1) + end. + lookup_record(Records, Tag, Arity) -> case erl_types:lookup_record(Tag, Arity, Records) of {ok, Fields} -> |