1 files changed, 116 insertions, 0 deletions
diff --git a/lib/redmine/nested_set/traversing.rb b/lib/redmine/nested_set/traversing.rb
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+++ b/lib/redmine/nested_set/traversing.rb
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+# Redmine - project management software
+# Copyright (C) 2006-2014  Jean-Philippe Lang
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+module Redmine
+  module NestedSet
+    module Traversing
+      def self.included(base)
+        base.class_eval do
+          scope :roots, lambda {where :parent_id => nil}
+          scope :leaves, lambda {where "#{table_name}.rgt - #{table_name}.lft = ?", 1}
+        end
+      end
+
+      # Returns true if the element has no parent
+      def root?
+        parent_id.nil?
+      end
+
+      # Returns true if the element has a parent
+      def child?
+        !root?
+      end
+
+      # Returns true if the element has no children
+      def leaf?
+        new_record? || (rgt - lft == 1)
+      end
+
+      # Returns the root element (ancestor with no parent)
+      def root
+        self_and_ancestors.first
+      end
+
+      # Returns the children
+      def children
+        if id.nil?
+          nested_set_scope.none
+        else
+          self.class.order(:lft).where(:parent_id => id)
+        end
+      end
+
+      # Returns the descendants that have no children
+      def leaves
+        descendants.where("#{self.class.table_name}.rgt - #{self.class.table_name}.lft = ?", 1)
+      end
+
+      # Returns the siblings
+      def siblings
+        nested_set_scope.where(:parent_id => parent_id).where("id <> ?", id)
+      end
+
+      # Returns the ancestors
+      def ancestors
+        if root?
+          nested_set_scope.none
+        else
+          nested_set_scope.where("#{self.class.table_name}.lft < ? AND #{self.class.table_name}.rgt > ?", lft, rgt)
+        end
+      end
+
+      # Returns the element and its ancestors
+      def self_and_ancestors
+        nested_set_scope.where("#{self.class.table_name}.lft <= ? AND #{self.class.table_name}.rgt >= ?", lft, rgt)
+      end
+
+      # Returns true if the element is an ancestor of other
+      def is_ancestor_of?(other)
+        same_nested_set_scope?(other) && other.lft > lft && other.rgt < rgt
+      end
+
+      # Returns true if the element equals other or is an ancestor of other
+      def is_or_is_ancestor_of?(other)
+        other == self || is_ancestor_of?(other)
+      end
+
+      # Returns the descendants
+      def descendants
+        if leaf?
+          nested_set_scope.none
+        else
+          nested_set_scope.where("#{self.class.table_name}.lft > ? AND #{self.class.table_name}.rgt < ?", lft, rgt)
+        end
+      end
+
+      # Returns the element and its descendants
+      def self_and_descendants
+        nested_set_scope.where("#{self.class.table_name}.lft >= ? AND #{self.class.table_name}.rgt <= ?", lft, rgt)
+      end
+
+      # Returns true if the element is a descendant of other
+      def is_descendant_of?(other)
+        same_nested_set_scope?(other) && other.lft < lft && other.rgt > rgt
+      end
+
+      # Returns true if the element equals other or is a descendant of other
+      def is_or_is_descendant_of?(other)
+        other == self || is_descendant_of?(other)
+      end
+    end
+  end
+end