Mercurial > hg > soundsoftware-site
diff .svn/pristine/34/345b699f46121e103fdce4587bf3ec87db1cc445.svn-base @ 1298:4f746d8966dd redmine_2.3_integration
Merge from redmine-2.3 branch to create new branch redmine-2.3-integration
author | Chris Cannam |
---|---|
date | Fri, 14 Jun 2013 09:28:30 +0100 |
parents | 622f24f53b42 |
children |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/.svn/pristine/34/345b699f46121e103fdce4587bf3ec87db1cc445.svn-base Fri Jun 14 09:28:30 2013 +0100 @@ -0,0 +1,107 @@ +module ActiveRecord + module Acts + module Tree + def self.included(base) + base.extend(ClassMethods) + end + + # Specify this +acts_as+ extension if you want to model a tree structure by providing a parent association and a children + # association. This requires that you have a foreign key column, which by default is called +parent_id+. + # + # class Category < ActiveRecord::Base + # acts_as_tree :order => "name" + # end + # + # Example: + # root + # \_ child1 + # \_ subchild1 + # \_ subchild2 + # + # root = Category.create("name" => "root") + # child1 = root.children.create("name" => "child1") + # subchild1 = child1.children.create("name" => "subchild1") + # + # root.parent # => nil + # child1.parent # => root + # root.children # => [child1] + # root.children.first.children.first # => subchild1 + # + # In addition to the parent and children associations, the following instance methods are added to the class + # after calling <tt>acts_as_tree</tt>: + # * <tt>siblings</tt> - Returns all the children of the parent, excluding the current node (<tt>[subchild2]</tt> when called on <tt>subchild1</tt>) + # * <tt>self_and_siblings</tt> - Returns all the children of the parent, including the current node (<tt>[subchild1, subchild2]</tt> when called on <tt>subchild1</tt>) + # * <tt>ancestors</tt> - Returns all the ancestors of the current node (<tt>[child1, root]</tt> when called on <tt>subchild2</tt>) + # * <tt>root</tt> - Returns the root of the current node (<tt>root</tt> when called on <tt>subchild2</tt>) + module ClassMethods + # Configuration options are: + # + # * <tt>foreign_key</tt> - specifies the column name to use for tracking of the tree (default: +parent_id+) + # * <tt>order</tt> - makes it possible to sort the children according to this SQL snippet. + # * <tt>counter_cache</tt> - keeps a count in a +children_count+ column if set to +true+ (default: +false+). + def acts_as_tree(options = {}) + configuration = { :foreign_key => "parent_id", :dependent => :destroy, :order => nil, :counter_cache => nil } + configuration.update(options) if options.is_a?(Hash) + + belongs_to :parent, :class_name => name, :foreign_key => configuration[:foreign_key], :counter_cache => configuration[:counter_cache] + has_many :children, :class_name => name, :foreign_key => configuration[:foreign_key], :order => configuration[:order], :dependent => configuration[:dependent] + + scope :roots, where("#{configuration[:foreign_key]} IS NULL").order(configuration[:order]) + + send :include, ActiveRecord::Acts::Tree::InstanceMethods + end + end + + module InstanceMethods + # Returns list of ancestors, starting from parent until root. + # + # subchild1.ancestors # => [child1, root] + def ancestors + node, nodes = self, [] + nodes << node = node.parent while node.parent + nodes + end + + # Returns list of descendants. + # + # root.descendants # => [child1, subchild1, subchild2] + def descendants(depth=nil) + depth ||= 0 + result = children.dup + unless depth == 1 + result += children.collect {|child| child.descendants(depth-1)}.flatten + end + result + end + + # Returns list of descendants and a reference to the current node. + # + # root.self_and_descendants # => [root, child1, subchild1, subchild2] + def self_and_descendants(depth=nil) + [self] + descendants(depth) + end + + # Returns the root node of the tree. + def root + node = self + node = node.parent while node.parent + node + end + + # Returns all siblings of the current node. + # + # subchild1.siblings # => [subchild2] + def siblings + self_and_siblings - [self] + end + + # Returns all siblings and a reference to the current node. + # + # subchild1.self_and_siblings # => [subchild1, subchild2] + def self_and_siblings + parent ? parent.children : self.class.roots + end + end + end + end +end