--- /dev/null
+use strict;
+use warnings;
+
+use Test::More;
+use Test::Exception;
+
+{
+
+ package Foo;
+ use Moose;
+ use Moose::Util::TypeConstraints;
+
+ subtype 'UCHash', as 'HashRef[Str]', where {
+ !grep {/[a-z]/} values %{$_};
+ };
+
+ coerce 'UCHash', from 'HashRef[Str]', via {
+ $_ = uc $_ for values %{$_};
+ $_;
+ };
+
+ has hash => (
+ traits => ['Hash'],
+ is => 'rw',
+ isa => 'UCHash',
+ coerce => 1,
+ handles => {
+ set_key => 'set',
+ },
+ );
+
+ our @TriggerArgs;
+
+ has lazy => (
+ traits => ['Hash'],
+ is => 'rw',
+ isa => 'UCHash',
+ coerce => 1,
+ lazy => 1,
+ default => sub { { x => 'a' } },
+ handles => {
+ set_lazy => 'set',
+ },
+ trigger => sub { @TriggerArgs = @_ },
+ clearer => 'clear_lazy',
+ );
+}
+
+my $foo = Foo->new;
+
+{
+ $foo->hash( { x => 'A', y => 'B' } );
+
+ $foo->set_key( z => 'c' );
+
+ is_deeply(
+ $foo->hash, { x => 'A', y => 'B', z => 'C' },
+ 'set coerces the hash'
+ );
+}
+
+{
+ $foo->set_lazy( y => 'b' );
+
+ is_deeply(
+ $foo->lazy, { x => 'A', y => 'B' },
+ 'set coerces the hash - lazy'
+ );
+
+ is_deeply(
+ \@Foo::TriggerArgs,
+ [ $foo, { x => 'A', y => 'B' }, { x => 'A' } ],
+ 'trigger receives expected arguments'
+ );
+}
+
+done_testing;