dialyzer: Print constraints using the '::' syntax

6 files changed, 34 insertions, 28 deletions

diff --git a/lib/dialyzer/src/dialyzer_contracts.erl b/lib/dialyzer/src/dialyzer_contracts.erl
index 7251de8b10..83b3ef72f2 100644
--- a/lib/dialyzer/src/dialyzer_contracts.erl
+++ b/lib/dialyzer/src/dialyzer_contracts.erl
@@ -126,13 +126,19 @@ butlast([H|T]) -> [H|butlast(T)].
 
 constraints_to_string([]) ->
   "";
-constraints_to_string([{type, _, constraint, [{atom, _, What}, Types]}]) ->
-  atom_to_list(What) ++ "(" ++
-    sequence([erl_types:t_form_to_string(T) || T <- Types], ",") ++ ")";
 constraints_to_string([{type, _, constraint, [{atom, _, What}, Types]}|Rest]) ->
-  atom_to_list(What) ++ "(" ++
-    sequence([erl_types:t_form_to_string(T) || T <- Types], ",")
-    ++ "), " ++ constraints_to_string(Rest).
+  S = constraint_to_string(What, Types),
+  case Rest of
+    [] -> S;
+    _ -> S ++ ", " ++ constraints_to_string(Rest)
+  end.
+
+constraint_to_string(is_subtype, [{var, _, Var}, T]) ->
+  atom_to_list(Var) ++ " :: " ++ erl_types:t_form_to_string(T);
+constraint_to_string(What, Types) ->
+  atom_to_list(What) ++ "("
+    ++ sequence([erl_types:t_form_to_string(T) || T <- Types], ",")
+    ++ ")".
 
 sequence([], _Delimiter) -> "";
 sequence([H], _Delimiter) -> H;
diff --git a/lib/dialyzer/test/r9c_SUITE_data/results/mnesia b/lib/dialyzer/test/r9c_SUITE_data/results/mnesia
index 1dc5a105bf..220b18ca7a 100644
--- a/lib/dialyzer/test/r9c_SUITE_data/results/mnesia
+++ b/lib/dialyzer/test/r9c_SUITE_data/results/mnesia
@@ -6,7 +6,7 @@ mnesia_bup.erl:111: The created fun has no local return
 mnesia_bup.erl:574: Function fallback_receiver/2 has no local return
 mnesia_bup.erl:967: Function uninstall_fallback_master/2 has no local return
 mnesia_checkpoint.erl:1014: The variable Error can never match since previous clauses completely covered the type {'ok',#checkpoint_args{nodes::[any()],retainers::[any(),...]}}
-mnesia_checkpoint.erl:894: The call sys:handle_system_msg(Msg::any(),From::any(),'no_parent','mnesia_checkpoint',[],Cp::#checkpoint_args{}) breaks the contract (Msg,From,Parent,Module,Debug,Misc) -> no_return() when is_subtype(Msg,term()), is_subtype(From,{pid(),Tag::_}), is_subtype(Parent,pid()), is_subtype(Module,module()), is_subtype(Debug,[dbg_opt()]), is_subtype(Misc,term())
+mnesia_checkpoint.erl:894: The call sys:handle_system_msg(Msg::any(),From::any(),'no_parent','mnesia_checkpoint',[],Cp::#checkpoint_args{}) breaks the contract (Msg,From,Parent,Module,Debug,Misc) -> no_return() when Msg :: term(), From :: {pid(),Tag::_}, Parent :: pid(), Module :: module(), Debug :: [dbg_opt()], Misc :: term()
 mnesia_controller.erl:1666: The variable Tab can never match since previous clauses completely covered the type [any()]
 mnesia_controller.erl:1679: The pattern {'stop', Reason, Reply, State2} can never match the type {'noreply',_} | {'reply',_,_} | {'stop','shutdown',#state{}}
 mnesia_controller.erl:1685: The pattern {'noreply', State2, _Timeout} can never match the type {'reply',_,_}
diff --git a/lib/dialyzer/test/small_SUITE_data/results/contracts_with_subtypes b/lib/dialyzer/test/small_SUITE_data/results/contracts_with_subtypes
index a9fbfb6068..d2a3ebb766 100644
--- a/lib/dialyzer/test/small_SUITE_data/results/contracts_with_subtypes
+++ b/lib/dialyzer/test/small_SUITE_data/results/contracts_with_subtypes
@@ -1,15 +1,15 @@
 
-contracts_with_subtypes.erl:106: The call contracts_with_subtypes:rec_arg({'a','b'}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,{'a',A} | {'b',B}), is_subtype(A,'a' | {'b',B}), is_subtype(B,'b' | {'a',A})
-contracts_with_subtypes.erl:107: The call contracts_with_subtypes:rec_arg({'b','a'}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,{'a',A} | {'b',B}), is_subtype(A,'a' | {'b',B}), is_subtype(B,'b' | {'a',A})
-contracts_with_subtypes.erl:109: The call contracts_with_subtypes:rec_arg({'b',{'a','b'}}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,{'a',A} | {'b',B}), is_subtype(A,'a' | {'b',B}), is_subtype(B,'b' | {'a',A})
-contracts_with_subtypes.erl:135: The call contracts_with_subtypes:rec2({'a','b'}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,ab())
-contracts_with_subtypes.erl:136: The call contracts_with_subtypes:rec2({'b','a'}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,ab())
-contracts_with_subtypes.erl:137: The call contracts_with_subtypes:rec2({'a',{'b','a'}}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,ab())
-contracts_with_subtypes.erl:138: The call contracts_with_subtypes:rec2({'b',{'a','b'}}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,ab())
-contracts_with_subtypes.erl:139: The call contracts_with_subtypes:rec2({'a',{'b',{'a','b'}}}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,ab())
-contracts_with_subtypes.erl:140: The call contracts_with_subtypes:rec2({'b',{'a',{'b','a'}}}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,ab())
-contracts_with_subtypes.erl:141: The call contracts_with_subtypes:rec2({'a',{'b',{'a',{'b','a'}}}}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,ab())
-contracts_with_subtypes.erl:142: The call contracts_with_subtypes:rec2({'b',{'a',{'b',{'a','b'}}}}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,ab())
+contracts_with_subtypes.erl:106: The call contracts_with_subtypes:rec_arg({'a','b'}) breaks the contract (Arg) -> 'ok' when Arg :: {'a',A} | {'b',B}, A :: 'a' | {'b',B}, B :: 'b' | {'a',A}
+contracts_with_subtypes.erl:107: The call contracts_with_subtypes:rec_arg({'b','a'}) breaks the contract (Arg) -> 'ok' when Arg :: {'a',A} | {'b',B}, A :: 'a' | {'b',B}, B :: 'b' | {'a',A}
+contracts_with_subtypes.erl:109: The call contracts_with_subtypes:rec_arg({'b',{'a','b'}}) breaks the contract (Arg) -> 'ok' when Arg :: {'a',A} | {'b',B}, A :: 'a' | {'b',B}, B :: 'b' | {'a',A}
+contracts_with_subtypes.erl:135: The call contracts_with_subtypes:rec2({'a','b'}) breaks the contract (Arg) -> 'ok' when Arg :: ab()
+contracts_with_subtypes.erl:136: The call contracts_with_subtypes:rec2({'b','a'}) breaks the contract (Arg) -> 'ok' when Arg :: ab()
+contracts_with_subtypes.erl:137: The call contracts_with_subtypes:rec2({'a',{'b','a'}}) breaks the contract (Arg) -> 'ok' when Arg :: ab()
+contracts_with_subtypes.erl:138: The call contracts_with_subtypes:rec2({'b',{'a','b'}}) breaks the contract (Arg) -> 'ok' when Arg :: ab()
+contracts_with_subtypes.erl:139: The call contracts_with_subtypes:rec2({'a',{'b',{'a','b'}}}) breaks the contract (Arg) -> 'ok' when Arg :: ab()
+contracts_with_subtypes.erl:140: The call contracts_with_subtypes:rec2({'b',{'a',{'b','a'}}}) breaks the contract (Arg) -> 'ok' when Arg :: ab()
+contracts_with_subtypes.erl:141: The call contracts_with_subtypes:rec2({'a',{'b',{'a',{'b','a'}}}}) breaks the contract (Arg) -> 'ok' when Arg :: ab()
+contracts_with_subtypes.erl:142: The call contracts_with_subtypes:rec2({'b',{'a',{'b',{'a','b'}}}}) breaks the contract (Arg) -> 'ok' when Arg :: ab()
 contracts_with_subtypes.erl:175: The pattern 1 can never match the type string()
 contracts_with_subtypes.erl:178: The pattern 'alpha' can never match the type {'ok',_} | {'ok',_,string()}
 contracts_with_subtypes.erl:180: The pattern 42 can never match the type {'ok',_} | {'ok',_,string()}
@@ -24,13 +24,13 @@ contracts_with_subtypes.erl:23: Invalid type specification for function contract
 contracts_with_subtypes.erl:240: The pattern {'ok', 42} can never match the type {'ok',_,string()}
 contracts_with_subtypes.erl:241: The pattern 42 can never match the type {'ok',_,string()}
 contracts_with_subtypes.erl:267: Function flat_ets_new_t/0 has no local return
-contracts_with_subtypes.erl:268: The call contracts_with_subtypes:flat_ets_new(12,[]) breaks the contract (Name,Options) -> atom() when is_subtype(Name,atom()), is_subtype(Options,[Option]), is_subtype(Option,'set' | 'ordered_set' | 'bag' | 'duplicate_bag' | 'public' | 'protected' | 'private' | 'named_table' | {'keypos',integer()} | {'heir',pid(),term()} | {'heir','none'} | {'write_concurrency',boolean()} | {'read_concurrency',boolean()} | 'compressed')
+contracts_with_subtypes.erl:268: The call contracts_with_subtypes:flat_ets_new(12,[]) breaks the contract (Name,Options) -> atom() when Name :: atom(), Options :: [Option], Option :: 'set' | 'ordered_set' | 'bag' | 'duplicate_bag' | 'public' | 'protected' | 'private' | 'named_table' | {'keypos',integer()} | {'heir',pid(),term()} | {'heir','none'} | {'write_concurrency',boolean()} | {'read_concurrency',boolean()} | 'compressed'
 contracts_with_subtypes.erl:294: Function factored_ets_new_t/0 has no local return
-contracts_with_subtypes.erl:295: The call contracts_with_subtypes:factored_ets_new(12,[]) breaks the contract (Name,Options) -> atom() when is_subtype(Name,atom()), is_subtype(Options,[Option]), is_subtype(Option,Type | Access | 'named_table' | {'keypos',Pos} | {'heir',Pid::pid(),HeirData} | {'heir','none'} | Tweaks), is_subtype(Type,type()), is_subtype(Access,access()), is_subtype(Tweaks,{'write_concurrency',boolean()} | {'read_concurrency',boolean()} | 'compressed'), is_subtype(Pos,pos_integer()), is_subtype(HeirData,term())
-contracts_with_subtypes.erl:77: The call contracts_with_subtypes:foo1(5) breaks the contract (Arg1) -> Res when is_subtype(Arg1,atom()), is_subtype(Res,atom())
-contracts_with_subtypes.erl:78: The call contracts_with_subtypes:foo2(5) breaks the contract (Arg1) -> Res when is_subtype(Arg1,Arg2), is_subtype(Arg2,atom()), is_subtype(Res,atom())
-contracts_with_subtypes.erl:79: The call contracts_with_subtypes:foo3(5) breaks the contract (Arg1) -> Res when is_subtype(Arg2,atom()), is_subtype(Arg1,Arg2), is_subtype(Res,atom())
+contracts_with_subtypes.erl:295: The call contracts_with_subtypes:factored_ets_new(12,[]) breaks the contract (Name,Options) -> atom() when Name :: atom(), Options :: [Option], Option :: Type | Access | 'named_table' | {'keypos',Pos} | {'heir',Pid::pid(),HeirData} | {'heir','none'} | Tweaks, Type :: type(), Access :: access(), Tweaks :: {'write_concurrency',boolean()} | {'read_concurrency',boolean()} | 'compressed', Pos :: pos_integer(), HeirData :: term()
+contracts_with_subtypes.erl:77: The call contracts_with_subtypes:foo1(5) breaks the contract (Arg1) -> Res when Arg1 :: atom(), Res :: atom()
+contracts_with_subtypes.erl:78: The call contracts_with_subtypes:foo2(5) breaks the contract (Arg1) -> Res when Arg1 :: Arg2, Arg2 :: atom(), Res :: atom()
+contracts_with_subtypes.erl:79: The call contracts_with_subtypes:foo3(5) breaks the contract (Arg1) -> Res when Arg2 :: atom(), Arg1 :: Arg2, Res :: atom()
 contracts_with_subtypes.erl:7: Invalid type specification for function contracts_with_subtypes:extract/0. The success typing is () -> 'something'
-contracts_with_subtypes.erl:80: The call contracts_with_subtypes:foo4(5) breaks the contract (Type) -> Type when is_subtype(Type,atom())
+contracts_with_subtypes.erl:80: The call contracts_with_subtypes:foo4(5) breaks the contract (Type) -> Type when Type :: atom()
 contracts_with_subtypes.erl:81: The call contracts_with_subtypes:foo5(5) breaks the contract (Type::atom()) -> Type::atom()
-contracts_with_subtypes.erl:82: The call contracts_with_subtypes:foo6(5) breaks the contract (Type) -> Type when is_subtype(Type,atom())
+contracts_with_subtypes.erl:82: The call contracts_with_subtypes:foo6(5) breaks the contract (Type) -> Type when Type :: atom()
diff --git a/lib/dialyzer/test/small_SUITE_data/results/contracts_with_subtypes2 b/lib/dialyzer/test/small_SUITE_data/results/contracts_with_subtypes2
index 9f5433a13d..1a8aeb13d0 100644
--- a/lib/dialyzer/test/small_SUITE_data/results/contracts_with_subtypes2
+++ b/lib/dialyzer/test/small_SUITE_data/results/contracts_with_subtypes2
@@ -1,3 +1,3 @@
 
 contracts_with_subtypes2.erl:18: Function t/0 has no local return
-contracts_with_subtypes2.erl:19: The call contracts_with_subtypes2:t({'a',{'b',{'c',{'d',{'e',{'g',3}}}}}}) breaks the contract (Arg) -> 'ok' when is_subtype(Arg,{'a',A}), is_subtype(A,{'b',B}), is_subtype(B,{'c',C}), is_subtype(C,{'d',D}), is_subtype(D,{'e',E}), is_subtype(E,{'f',_})
+contracts_with_subtypes2.erl:19: The call contracts_with_subtypes2:t({'a',{'b',{'c',{'d',{'e',{'g',3}}}}}}) breaks the contract (Arg) -> 'ok' when Arg :: {'a',A}, A :: {'b',B}, B :: {'c',C}, C :: {'d',D}, D :: {'e',E}, E :: {'f',_}
diff --git a/lib/dialyzer/test/small_SUITE_data/results/pretty_bitstring b/lib/dialyzer/test/small_SUITE_data/results/pretty_bitstring
index 0ad6eee766..e148e5cf22 100644
--- a/lib/dialyzer/test/small_SUITE_data/results/pretty_bitstring
+++ b/lib/dialyzer/test/small_SUITE_data/results/pretty_bitstring
@@ -1,3 +1,3 @@
 
 pretty_bitstring.erl:7: Function t/0 has no local return
-pretty_bitstring.erl:8: The call binary:copy(#{#<1>(8, 1, 'integer', ['unsigned', 'big']), #<2>(8, 1, 'integer', ['unsigned', 'big']), #<3>(3, 1, 'integer', ['unsigned', 'big'])}#,2) breaks the contract (Subject,N) -> binary() when is_subtype(Subject,binary()), is_subtype(N,non_neg_integer())
+pretty_bitstring.erl:8: The call binary:copy(#{#<1>(8, 1, 'integer', ['unsigned', 'big']), #<2>(8, 1, 'integer', ['unsigned', 'big']), #<3>(3, 1, 'integer', ['unsigned', 'big'])}#,2) breaks the contract (Subject,N) -> binary() when Subject :: binary(), N :: non_neg_integer()
diff --git a/lib/dialyzer/test/user_SUITE_data/results/wsp_pdu b/lib/dialyzer/test/user_SUITE_data/results/wsp_pdu
index d1f8f4caf2..626e677524 100644
--- a/lib/dialyzer/test/user_SUITE_data/results/wsp_pdu
+++ b/lib/dialyzer/test/user_SUITE_data/results/wsp_pdu
@@ -6,7 +6,7 @@ wsp_pdu.erl:2403: The call wsp_pdu:d_date(Data1::binary()) will never return sin
 wsp_pdu.erl:2406: Guard test is_integer(Sec::{[byte()] | byte() | {'long',binary()} | {'short',binary()},binary()}) can never succeed
 wsp_pdu.erl:2408: The pattern {'short', Data2} can never match the type {[byte()] | byte() | {'long',binary()} | {'short',binary()},binary()}
 wsp_pdu.erl:2755: Function parse_push_flag/1 has no local return
-wsp_pdu.erl:2756: The call erlang:integer_to_list(Value::[any()]) breaks the contract (Integer) -> string() when is_subtype(Integer,integer())
+wsp_pdu.erl:2756: The call erlang:integer_to_list(Value::[any()]) breaks the contract (Integer) -> string() when Integer :: integer()
 wsp_pdu.erl:2875: The call wsp_pdu:d_text_string(Data::byte()) will never return since it differs in the 1st argument from the success typing arguments: (binary())
 wsp_pdu.erl:2976: The call wsp_pdu:d_q_value(QData::byte()) will never return since it differs in the 1st argument from the success typing arguments: (<<_:8,_:_*8>>)
 wsp_pdu.erl:3336: The call wsp_pdu:encode_typed_field(Ver::any(),'Q-value',ParamValue::any()) will never return since it differs in the 2nd argument from the success typing arguments: (any(),'Constrained-encoding' | 'Date-value' | 'No-value' | 'Short-integer' | 'Text-string' | 'Text-value' | 'Well-known-charset',any())