comparison .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
comparison
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1297:0a574315af3e 1298:4f746d8966dd
1 module ActiveRecord
2 module Acts
3 module Tree
4 def self.included(base)
5 base.extend(ClassMethods)
6 end
7
8 # Specify this +acts_as+ extension if you want to model a tree structure by providing a parent association and a children
9 # association. This requires that you have a foreign key column, which by default is called +parent_id+.
10 #
11 # class Category < ActiveRecord::Base
12 # acts_as_tree :order => "name"
13 # end
14 #
15 # Example:
16 # root
17 # \_ child1
18 # \_ subchild1
19 # \_ subchild2
20 #
21 # root = Category.create("name" => "root")
22 # child1 = root.children.create("name" => "child1")
23 # subchild1 = child1.children.create("name" => "subchild1")
24 #
25 # root.parent # => nil
26 # child1.parent # => root
27 # root.children # => [child1]
28 # root.children.first.children.first # => subchild1
29 #
30 # In addition to the parent and children associations, the following instance methods are added to the class
31 # after calling <tt>acts_as_tree</tt>:
32 # * <tt>siblings</tt> - Returns all the children of the parent, excluding the current node (<tt>[subchild2]</tt> when called on <tt>subchild1</tt>)
33 # * <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>)
34 # * <tt>ancestors</tt> - Returns all the ancestors of the current node (<tt>[child1, root]</tt> when called on <tt>subchild2</tt>)
35 # * <tt>root</tt> - Returns the root of the current node (<tt>root</tt> when called on <tt>subchild2</tt>)
36 module ClassMethods
37 # Configuration options are:
38 #
39 # * <tt>foreign_key</tt> - specifies the column name to use for tracking of the tree (default: +parent_id+)
40 # * <tt>order</tt> - makes it possible to sort the children according to this SQL snippet.
41 # * <tt>counter_cache</tt> - keeps a count in a +children_count+ column if set to +true+ (default: +false+).
42 def acts_as_tree(options = {})
43 configuration = { :foreign_key => "parent_id", :dependent => :destroy, :order => nil, :counter_cache => nil }
44 configuration.update(options) if options.is_a?(Hash)
45
46 belongs_to :parent, :class_name => name, :foreign_key => configuration[:foreign_key], :counter_cache => configuration[:counter_cache]
47 has_many :children, :class_name => name, :foreign_key => configuration[:foreign_key], :order => configuration[:order], :dependent => configuration[:dependent]
48
49 scope :roots, where("#{configuration[:foreign_key]} IS NULL").order(configuration[:order])
50
51 send :include, ActiveRecord::Acts::Tree::InstanceMethods
52 end
53 end
54
55 module InstanceMethods
56 # Returns list of ancestors, starting from parent until root.
57 #
58 # subchild1.ancestors # => [child1, root]
59 def ancestors
60 node, nodes = self, []
61 nodes << node = node.parent while node.parent
62 nodes
63 end
64
65 # Returns list of descendants.
66 #
67 # root.descendants # => [child1, subchild1, subchild2]
68 def descendants(depth=nil)
69 depth ||= 0
70 result = children.dup
71 unless depth == 1
72 result += children.collect {|child| child.descendants(depth-1)}.flatten
73 end
74 result
75 end
76
77 # Returns list of descendants and a reference to the current node.
78 #
79 # root.self_and_descendants # => [root, child1, subchild1, subchild2]
80 def self_and_descendants(depth=nil)
81 [self] + descendants(depth)
82 end
83
84 # Returns the root node of the tree.
85 def root
86 node = self
87 node = node.parent while node.parent
88 node
89 end
90
91 # Returns all siblings of the current node.
92 #
93 # subchild1.siblings # => [subchild2]
94 def siblings
95 self_and_siblings - [self]
96 end
97
98 # Returns all siblings and a reference to the current node.
99 #
100 # subchild1.self_and_siblings # => [subchild1, subchild2]
101 def self_and_siblings
102 parent ? parent.children : self.class.roots
103 end
104 end
105 end
106 end
107 end