rails / acts_as_tree

NOTICE: official repository moved to https://github.com/amerine/acts_as_tree

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acts_as_tree's Issues

support for autosave

I'd like to be able to use :autosave => true in the has_many :children association created by acts_as_tree so that I an modify a tree of objects and save them all from a single update_attributes call.

Usefull methods?

Hi. What about adding some usefull methods to your plug in:
leafs: returns only the last elements of a tree for a given knot
structure: returns the given knot and all elements under the knot

Hereby a suggestion of code - it works pretty nice:

module ActiveRecord
module Acts
module Tree
module ClassMethods
def structure(knot=find(0)) #Returns an array of knot and all elements under knot
y = Array.new
y[0] = knot
if y[0].children.first then
looping(y, knot)
end
return y
end
def leafs(knot=find(0)) #Returns only the last elements of your tree under the tree object knot
@@tmp = structure(knot)
@leafs = Array.new
@@tmp.each do |i|
if not (i.children.first) then
@leafs[@leafs.size] = i
end
end
return @leafs
end
private
def looping(y, parent)
t = Array.new
t = parent.children
t.each do |i|
y[y.size] = i
if i.children.first then
looping(y, i)
end
end
end
end
end
end
end

Graph like behaviour

I can store a relation that is a graph in fact. Is it expected? I think it should throw an exception when there is a recycling path (For example A->B->A->B....). Here is the test (please note that this test passes; however i am expecting it to fail):

category = Category.new
category.name="Parent"
category.save
child = category.children.create("name" => "child_1")
child.children = [category]
assert category.save
loadedChild = Category.find_by_name("child_1")
assert_equal "Parent", loadedChild.parent.name
assert_equal "Parent", loadedChild.children[0].name

I added following code snippet to my domain object: (i am new to ruby so may be this is not the best way)

Although this seems alright with unit tests; when i test manually from browser; server dies due to infinite loop i guess.

validate :validate_recycling

def validate_recycling
begin
check_recycling []
rescue ArgumentError => msg
errors.add(:base, msg.message)
end
end

def check_recycling(parents)
raise ArgumentError, "#{self.name} is recycling!" if parents.include?(self)
copy = parents.dup
copy.push self
children.each { |child| child.check_recycling(copy) }
end

I guess the problem is before to validation, following lines (i found in the source code of the gem i installed) may run forever:

nodes << node = node.parent while node.parent

While loops have no recursion protection

If a page has one of its children defined as its parent, the methods 'root' and 'ancestors' will cause a time out.
Perhaps add error handling for if a node has already been in the loop, or just a limit to the number of levels to traverse.

Does not work with Rails 2.3.8

In ActiveSupport 2.3.8, the parent method is defined in the Module class which conflicts with the acts_as_tree parent method.

http://github.com/rails/rails/blob/v2.3.8/activesupport/lib/active_support/core_ext/module/introspection.rb