is_* methods and primary key validation

[dbsrgits/DBIx-Class-Tree.git] / lib / DBIx / Class / Tree / AdjacencyList.pm

diff --git a/lib/DBIx/Class/Tree/AdjacencyList.pm b/lib/DBIx/Class/Tree/AdjacencyList.pm
index 4c9a758..58c0961 100644 (file)
--- a/lib/DBIx/Class/Tree/AdjacencyList.pm
+++ b/lib/DBIx/Class/Tree/AdjacencyList.pm
@@ -207,6 +207,67 @@ sub attach_sibling {
     return $return;
 }
 
+=head2 is_leaf
+
+  if ($obj->is_leaf()) { ... }
+
+Returns 1 if the object has no children, and 0 otherwise.
+
+=cut
+
+sub is_leaf {
+    my( $self ) = @_;
+    return $self->result_source->resultset->search(
+        { $self->_parent_column => $self->id() },
+        { limit => 1 }
+    )->count();
+}
+
+=head2 is_root
+
+  if ($obj->is_root()) { ... }
+
+Returns 1 if the object has no parent, and 0 otherwise.
+
+=cut
+
+sub is_root {
+    my( $self ) = @_;
+    return ( $self->get_column( $self->_parent_column ) ? 1 : 0 );
+}
+
+=head2 is_branch
+
+  if ($obj->is_branch()) { ... }
+
+Returns 1 if the object has a parent and has children.  
+Returns 0 otherwise.
+
+=cut
+
+sub is_branch {
+    my( $self ) = @_;
+    return ( ($self->is_leaf() or $self->is_root()) ? 0 : 1 );
+}
+
+=head2 set_primary_key
+
+This method is an override of DBIx::Class' method for setting the 
+class' primary key column(s).  This method passes control right on 
+to the normal method after first validating that only one column is 
+being selected as a primary key.  If more than one column is then 
+an error will be thrown.
+
+=cut
+
+sub set_primary_ley {
+    my $self = shift;
+    if (@_>1) {
+        croak('You may only specify a single column as the primary key for adjacency tree classes');
+    }
+    return $self->next::method( @_ );
+}
+
 1;
 __END__