Moose-2.1405HEADMoose-2.1405master

1 files changed, 174 insertions, 0 deletions

diff --git a/t/recipes/basics_binarytree_attributefeatures.t b/t/recipes/basics_binarytree_attributefeatures.t
new file mode 100644
index 0000000..87222fd
--- /dev/null
+++ b/t/recipes/basics_binarytree_attributefeatures.t
@@ -0,0 +1,174 @@
+#!/usr/bin/perl -w
+
+use strict;
+use Test::More 'no_plan';
+use Test::Fatal;
+$| = 1;
+
+
+
+# =begin testing SETUP
+{
+
+  package BinaryTree;
+  use Moose;
+
+  has 'node' => ( is => 'rw', isa => 'Any' );
+
+  has 'parent' => (
+      is        => 'rw',
+      isa       => 'BinaryTree',
+      predicate => 'has_parent',
+      weak_ref  => 1,
+  );
+
+  has 'left' => (
+      is        => 'rw',
+      isa       => 'BinaryTree',
+      predicate => 'has_left',
+      lazy      => 1,
+      default   => sub { BinaryTree->new( parent => $_[0] ) },
+      trigger   => \&_set_parent_for_child
+  );
+
+  has 'right' => (
+      is        => 'rw',
+      isa       => 'BinaryTree',
+      predicate => 'has_right',
+      lazy      => 1,
+      default   => sub { BinaryTree->new( parent => $_[0] ) },
+      trigger   => \&_set_parent_for_child
+  );
+
+  sub _set_parent_for_child {
+      my ( $self, $child ) = @_;
+
+      confess "You cannot insert a tree which already has a parent"
+          if $child->has_parent;
+
+      $child->parent($self);
+  }
+}
+
+
+
+# =begin testing
+{
+use Scalar::Util 'isweak';
+
+my $root = BinaryTree->new(node => 'root');
+isa_ok($root, 'BinaryTree');
+
+is($root->node, 'root', '... got the right node value');
+
+ok(!$root->has_left, '... no left node yet');
+ok(!$root->has_right, '... no right node yet');
+
+ok(!$root->has_parent, '... no parent for root node');
+
+# make a left node
+
+my $left = $root->left;
+isa_ok($left, 'BinaryTree');
+
+is($root->left, $left, '... got the same node (and it is $left)');
+ok($root->has_left, '... we have a left node now');
+
+ok($left->has_parent, '... lefts has a parent');
+is($left->parent, $root, '... lefts parent is the root');
+
+ok(isweak($left->{parent}), '... parent is a weakened ref');
+
+ok(!$left->has_left, '... $left no left node yet');
+ok(!$left->has_right, '... $left no right node yet');
+
+is($left->node, undef, '... left has got no node value');
+
+is(
+    exception {
+        $left->node('left');
+    },
+    undef,
+    '... assign to lefts node'
+);
+
+is($left->node, 'left', '... left now has a node value');
+
+# make a right node
+
+ok(!$root->has_right, '... still no right node yet');
+
+is($root->right->node, undef, '... right has got no node value');
+
+ok($root->has_right, '... now we have a right node');
+
+my $right = $root->right;
+isa_ok($right, 'BinaryTree');
+
+is(
+    exception {
+        $right->node('right');
+    },
+    undef,
+    '... assign to rights node'
+);
+
+is($right->node, 'right', '... left now has a node value');
+
+is($root->right, $right, '... got the same node (and it is $right)');
+ok($root->has_right, '... we have a right node now');
+
+ok($right->has_parent, '... rights has a parent');
+is($right->parent, $root, '... rights parent is the root');
+
+ok(isweak($right->{parent}), '... parent is a weakened ref');
+
+# make a left node of the left node
+
+my $left_left = $left->left;
+isa_ok($left_left, 'BinaryTree');
+
+ok($left_left->has_parent, '... left does have a parent');
+
+is($left_left->parent, $left, '... got a parent node (and it is $left)');
+ok($left->has_left, '... we have a left node now');
+is($left->left, $left_left, '... got a left node (and it is $left_left)');
+
+ok(isweak($left_left->{parent}), '... parent is a weakened ref');
+
+# make a right node of the left node
+
+my $left_right = BinaryTree->new;
+isa_ok($left_right, 'BinaryTree');
+
+is(
+    exception {
+        $left->right($left_right);
+    },
+    undef,
+    '... assign to rights node'
+);
+
+ok($left_right->has_parent, '... left does have a parent');
+
+is($left_right->parent, $left, '... got a parent node (and it is $left)');
+ok($left->has_right, '... we have a left node now');
+is($left->right, $left_right, '... got a left node (and it is $left_left)');
+
+ok(isweak($left_right->{parent}), '... parent is a weakened ref');
+
+# and check the error
+
+isnt(
+    exception {
+        $left_right->right($left_left);
+    },
+    undef,
+    '... cannot assign a node which already has a parent'
+);
+}
+
+
+
+
+1;