Any type fix within complex patterns (#315)

Any type fix within complex patterns

Author: Francois Brodeur

src/typechecker.erl

@@ -45,6 +45,7 @@
 -define(top(), {remote_type, _, [{atom,_,gradualizer}
 				,{atom,_,top},[]]}).
 -define(record_field(Name), {record_field, _, {atom, _, Name}, _}).
+-define(record_field_expr(Expr), {record_field, _, _, Expr}).
 -define(typed_record_field(Name), {typed_record_field, ?record_field(Name), _}).
 -define(typed_record_field(Name, Type), {typed_record_field, ?record_field(Name), Type}).
 -define(type_field_type(Name, Type), {type, _, field_type, [{atom, _, Name}, Type]}).
@@ -1175,6 +1176,8 @@ expect_record_type({var, _, Var}, Record, #tenv{records = REnv}) ->
         _NotFound ->
             {type_error, Record}
     end;
+expect_record_type({type, _, any, []}, _Record, _TEnv) ->
+    any;
 expect_record_type(_, Ty, _) ->
     {type_error, Ty}.
 
@@ -3711,8 +3714,6 @@ add_type_pat({var, _, A} = Var, Ty, TEnv, VEnv) ->
             %% Match all
 	    {Ty, Ty, VEnv#{A => Ty}, constraints:empty()}
     end;
-add_type_pat(Expr, {type, _, any, []} = Ty, _TEnv, VEnv) ->
-    {type(none), Ty, add_any_types_pat(Expr, VEnv), constraints:empty()};
 add_type_pat(Pat, ?type(union, UnionTys)=UnionTy, TEnv, VEnv) ->
     {PatTys, UBounds, VEnvs, Css} =
         lists:foldr(fun (Ty, {PatTysAcc, UBoundsAcc, VEnvAcc, CsAcc}=Acc) ->
@@ -3843,7 +3844,7 @@ add_type_pat({record, P, Record, Fields}, Ty, TEnv, VEnv) ->
         any ->
             {type(none)
                 ,Ty
-                ,union_var_binds([add_any_types_pat(Field, VEnv) || Field <- Fields], TEnv)
+                ,union_var_binds([add_any_types_pat(Field, VEnv) || ?record_field_expr(Field) <- Fields], TEnv)
                 ,constraints:empty()};
         {fields_ty, Tys, Cs} ->
             {PatTys, UBounds, VEnv1, Cs1} = add_type_pat_fields(Fields, Tys, TEnv, VEnv),

test/should_pass/records.erl

@@ -61,3 +61,6 @@ rec_index_subtype() ->
 -spec record_as_tuple(#r{}) -> tuple().
 record_as_tuple(R) ->
     R.
+
+-record(rec_any, {f}).
+f(#rec_any{f = F} = R) -> F.

test/should_pass/tuple_union_pat.erl

@@ -5,3 +5,11 @@
 -spec f(tuple() | integer()) -> ok.
 f({1, 2}) ->
     ok.
+
+-spec g({ok, binary()} | {error, term()}) -> integer().
+g({error, key_not_found} = _Response) ->
+    1;
+g({error, _} = _Response) ->
+    2;
+g({ok, _} = _Response) ->
+    3.

test/typechecker_tests.erl

@@ -562,7 +562,7 @@ add_type_pat_test_() ->
     [{"Pattern matching list against any()",
       ?_assert(type_check_forms(["f([E|_]) -> E."]))},
      {"Pattern matching record against any()",
-      ?_assert(type_check_forms(["-record(f, {r}).",
+      ?_assert(type_check_forms(["-record(r, {f}).",
                                  "f(#r{f = F}) -> F."]))}
     ].