1 files changed, 125 insertions, 0 deletions
diff --git a/t/examples/example1.t b/t/examples/example1.t
new file mode 100644
index 0000000..643b0cd
--- /dev/null
+++ b/t/examples/example1.t
@@ -0,0 +1,125 @@
+use strict;
+use warnings;
+
+use Test::More;
+
+
+## Roles
+
+{
+    package Constraint;
+    use Moose::Role;
+
+    has 'value' => (isa => 'Num', is => 'ro');
+
+    around 'validate' => sub {
+        my $c = shift;
+        my ($self, $field) = @_;
+        return undef if $c->($self, $self->validation_value($field));
+        return $self->error_message;
+    };
+
+    sub validation_value {
+        my ($self, $field) = @_;
+        return $field;
+    }
+
+    sub error_message { confess "Abstract method!" }
+
+    package Constraint::OnLength;
+    use Moose::Role;
+
+    has 'units' => (isa => 'Str', is => 'ro');
+
+    override 'validation_value' => sub {
+        return length(super());
+    };
+
+    override 'error_message' => sub {
+        my $self = shift;
+        return super() . ' ' . $self->units;
+    };
+
+}
+
+## Classes
+
+{
+    package Constraint::AtLeast;
+    use Moose;
+
+    with 'Constraint';
+
+    sub validate {
+        my ($self, $field) = @_;
+        ($field >= $self->value);
+    }
+
+    sub error_message { 'must be at least ' . (shift)->value; }
+
+    package Constraint::NoMoreThan;
+    use Moose;
+
+    with 'Constraint';
+
+    sub validate {
+        my ($self, $field) = @_;
+        ($field <= $self->value);
+    }
+
+    sub error_message { 'must be no more than ' . (shift)->value; }
+
+    package Constraint::LengthNoMoreThan;
+    use Moose;
+
+    extends 'Constraint::NoMoreThan';
+       with 'Constraint::OnLength';
+
+    package Constraint::LengthAtLeast;
+    use Moose;
+
+    extends 'Constraint::AtLeast';
+       with 'Constraint::OnLength';
+}
+
+my $no_more_than_10 = Constraint::NoMoreThan->new(value => 10);
+isa_ok($no_more_than_10, 'Constraint::NoMoreThan');
+
+ok($no_more_than_10->does('Constraint'), '... Constraint::NoMoreThan does Constraint');
+
+ok(!defined($no_more_than_10->validate(1)), '... validated correctly');
+is($no_more_than_10->validate(11), 'must be no more than 10', '... validation failed correctly');
+
+my $at_least_10 = Constraint::AtLeast->new(value => 10);
+isa_ok($at_least_10, 'Constraint::AtLeast');
+
+ok($at_least_10->does('Constraint'), '... Constraint::AtLeast does Constraint');
+
+ok(!defined($at_least_10->validate(11)), '... validated correctly');
+is($at_least_10->validate(1), 'must be at least 10', '... validation failed correctly');
+
+# onlength
+
+my $no_more_than_10_chars = Constraint::LengthNoMoreThan->new(value => 10, units => 'chars');
+isa_ok($no_more_than_10_chars, 'Constraint::LengthNoMoreThan');
+isa_ok($no_more_than_10_chars, 'Constraint::NoMoreThan');
+
+ok($no_more_than_10_chars->does('Constraint'), '... Constraint::LengthNoMoreThan does Constraint');
+ok($no_more_than_10_chars->does('Constraint::OnLength'), '... Constraint::LengthNoMoreThan does Constraint::OnLength');
+
+ok(!defined($no_more_than_10_chars->validate('foo')), '... validated correctly');
+is($no_more_than_10_chars->validate('foooooooooo'),
+    'must be no more than 10 chars',
+    '... validation failed correctly');
+
+my $at_least_10_chars = Constraint::LengthAtLeast->new(value => 10, units => 'chars');
+isa_ok($at_least_10_chars, 'Constraint::LengthAtLeast');
+isa_ok($at_least_10_chars, 'Constraint::AtLeast');
+
+ok($at_least_10_chars->does('Constraint'), '... Constraint::LengthAtLeast does Constraint');
+ok($at_least_10_chars->does('Constraint::OnLength'), '... Constraint::LengthAtLeast does Constraint::OnLength');
+
+ok(!defined($at_least_10_chars->validate('barrrrrrrrr')), '... validated correctly');
+is($at_least_10_chars->validate('bar'), 'must be at least 10 chars', '... validation failed correctly');
+
+done_testing;