--- /dev/null
+use strict;
+use warnings;
+use Test::More tests => 12;
+use Scalar::Util qw/blessed/;
+
+{
+ package Obj1;
+ sub new { bless {}, shift };
+}
+{
+ package Obj2;
+ use overload '""' => sub { 'Ref' }, fallback => 1;
+ sub new { bless {}, shift };
+}
+
+{
+ package Foo;
+ use Mouse;
+ use Mouse::Util::TypeConstraints;
+
+ subtype 'Type1' => as 'Str' => where { blessed($_) };
+ has str_obj => (
+ is => 'rw',
+ isa => 'Type1',
+ );
+
+ subtype 'Type2' => as 'Object' => where { $_ eq 'Ref' };
+ has obj_str => (
+ is => 'rw',
+ isa => 'Type2',
+ );
+
+ subtype 'Type3' => as 'Object';
+ has as_only => (
+ is => 'rw',
+ isa => 'Type3',
+ );
+
+
+ type 'Type4';
+ has any => (
+ is => 'rw',
+ isa => 'Type4',
+ );
+}
+
+eval { Foo->new( str_obj => Obj1->new ) };
+like $@, qr/Attribute \(str_obj\) does not pass the type constraint because: Validation failed for 'Type1' failed with value Obj1=HASH/;
+eval { Foo->new( obj_str => Obj1->new ) };
+like $@, qr/Attribute \(obj_str\) does not pass the type constraint because: Validation failed for 'Type2' failed with value Obj1=HASH/;
+
+eval { Foo->new( str_obj => Obj2->new ) };
+like $@, qr/Attribute \(str_obj\) does not pass the type constraint because: Validation failed for 'Type1' failed with value Obj2=HASH/;
+
+eval { Foo->new( str_obj => 'Ref' ) };
+like $@, qr/Attribute \(str_obj\) does not pass the type constraint because: Validation failed for 'Type1' failed with value Ref/;
+
+my $f1 = eval { Foo->new( obj_str => Obj2->new ) };
+isa_ok $f1, 'Foo';
+is $f1->obj_str, 'Ref';
+
+my $f2 = eval { Foo->new( as_only => Obj1->new ) };
+isa_ok $f2, 'Foo';
+is ref($f2->as_only), 'Obj1';
+
+my $f3 = eval { Foo->new( any => Obj1->new ) };
+die $@ if $@;
+isa_ok $f3, 'Foo';
+is ref($f3->any), 'Obj1';
+
+my $f4 = eval { Foo->new( any => 'YATTA' ) };
+isa_ok $f4, 'Foo';
+is $f4->any, 'YATTA';