773 lines
30 KiB
Ruby
773 lines
30 KiB
Ruby
module CollectiveIdea #:nodoc:
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module Acts #:nodoc:
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module NestedSet #:nodoc:
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# This acts provides Nested Set functionality. Nested Set is a smart way to implement
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# an _ordered_ tree, with the added feature that you can select the children and all of their
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# descendants with a single query. The drawback is that insertion or move need some complex
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# sql queries. But everything is done here by this module!
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#
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# Nested sets are appropriate each time you want either an orderd tree (menus,
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# commercial categories) or an efficient way of querying big trees (threaded posts).
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#
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# == API
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#
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# Methods names are aligned with acts_as_tree as much as possible to make replacment from one
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# by another easier.
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#
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# item.children.create(:name => "child1")
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#
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# Configuration options are:
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#
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# * +:parent_column+ - specifies the column name to use for keeping the position integer (default: parent_id)
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# * +:left_column+ - column name for left boundry data, default "lft"
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# * +:right_column+ - column name for right boundry data, default "rgt"
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# * +:depth_column+ - column name for the depth data, default "depth"
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# * +:scope+ - restricts what is to be considered a list. Given a symbol, it'll attach "_id"
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# (if it hasn't been already) and use that as the foreign key restriction. You
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# can also pass an array to scope by multiple attributes.
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# Example: <tt>acts_as_nested_set :scope => [:notable_id, :notable_type]</tt>
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# * +:dependent+ - behavior for cascading destroy. If set to :destroy, all the
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# child objects are destroyed alongside this object by calling their destroy
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# method. If set to :delete_all (default), all the child objects are deleted
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# without calling their destroy method.
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# * +:counter_cache+ adds a counter cache for the number of children.
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# defaults to false.
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# Example: <tt>acts_as_nested_set :counter_cache => :children_count</tt>
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# * +:order_column+ on which column to do sorting, by default it is the left_column_name
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# Example: <tt>acts_as_nested_set :order_column => :position</tt>
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#
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# See CollectiveIdea::Acts::NestedSet::Model::ClassMethods for a list of class methods and
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# CollectiveIdea::Acts::NestedSet::Model for a list of instance methods added
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# to acts_as_nested_set models
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def acts_as_nested_set(options = {})
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options = {
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:parent_column => 'parent_id',
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:left_column => 'lft',
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:right_column => 'rgt',
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:depth_column => 'depth',
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:dependent => :delete_all, # or :destroy
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:polymorphic => false,
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:counter_cache => false
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}.merge(options)
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if options[:scope].is_a?(Symbol) && options[:scope].to_s !~ /_id$/
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options[:scope] = "#{options[:scope]}_id".intern
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end
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class_attribute :acts_as_nested_set_options
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self.acts_as_nested_set_options = options
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include CollectiveIdea::Acts::NestedSet::Model
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include Columns
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extend Columns
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belongs_to :parent, :class_name => self.base_class.to_s,
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:foreign_key => parent_column_name,
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:counter_cache => options[:counter_cache],
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:inverse_of => (:children unless options[:polymorphic]),
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:polymorphic => options[:polymorphic]
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has_many_children_options = {
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:class_name => self.base_class.to_s,
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:foreign_key => parent_column_name,
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:order => order_column,
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:inverse_of => (:parent unless options[:polymorphic]),
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}
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# Add callbacks, if they were supplied.. otherwise, we don't want them.
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[:before_add, :after_add, :before_remove, :after_remove].each do |ar_callback|
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has_many_children_options.update(ar_callback => options[ar_callback]) if options[ar_callback]
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end
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has_many :children, has_many_children_options
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attr_accessor :skip_before_destroy
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before_create :set_default_left_and_right
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before_save :store_new_parent
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after_save :move_to_new_parent, :set_depth!
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before_destroy :destroy_descendants
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# no assignment to structure fields
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[left_column_name, right_column_name, depth_column_name].each do |column|
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module_eval <<-"end_eval", __FILE__, __LINE__
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def #{column}=(x)
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raise ActiveRecord::ActiveRecordError, "Unauthorized assignment to #{column}: it's an internal field handled by acts_as_nested_set code, use move_to_* methods instead."
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end
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end_eval
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end
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define_model_callbacks :move
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end
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module Model
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extend ActiveSupport::Concern
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included do
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delegate :quoted_table_name, :to => self
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end
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module ClassMethods
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# Returns the first root
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def root
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roots.first
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end
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def roots
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where(parent_column_name => nil).order(quoted_left_column_full_name)
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end
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def leaves
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where("#{quoted_right_column_full_name} - #{quoted_left_column_full_name} = 1").order(quoted_left_column_full_name)
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end
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def valid?
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left_and_rights_valid? && no_duplicates_for_columns? && all_roots_valid?
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end
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def left_and_rights_valid?
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## AS clause not supported in Oracle in FROM clause for aliasing table name
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joins("LEFT OUTER JOIN #{quoted_table_name}" +
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(connection.adapter_name.match(/Oracle/).nil? ? " AS " : " ") +
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"parent ON " +
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"#{quoted_parent_column_full_name} = parent.#{primary_key}").
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where(
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"#{quoted_left_column_full_name} IS NULL OR " +
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"#{quoted_right_column_full_name} IS NULL OR " +
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"#{quoted_left_column_full_name} >= " +
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"#{quoted_right_column_full_name} OR " +
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"(#{quoted_parent_column_full_name} IS NOT NULL AND " +
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"(#{quoted_left_column_full_name} <= parent.#{quoted_left_column_name} OR " +
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"#{quoted_right_column_full_name} >= parent.#{quoted_right_column_name}))"
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).count == 0
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end
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def no_duplicates_for_columns?
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scope_string = Array(acts_as_nested_set_options[:scope]).map do |c|
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connection.quote_column_name(c)
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end.push(nil).join(", ")
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[quoted_left_column_full_name, quoted_right_column_full_name].all? do |column|
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# No duplicates
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select("#{scope_string}#{column}, COUNT(#{column})").
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group("#{scope_string}#{column}").
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having("COUNT(#{column}) > 1").
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first.nil?
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end
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end
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# Wrapper for each_root_valid? that can deal with scope.
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def all_roots_valid?
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if acts_as_nested_set_options[:scope]
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roots.group_by {|record| scope_column_names.collect {|col| record.send(col.to_sym) } }.all? do |scope, grouped_roots|
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each_root_valid?(grouped_roots)
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end
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else
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each_root_valid?(roots)
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end
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end
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def each_root_valid?(roots_to_validate)
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left = right = 0
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roots_to_validate.all? do |root|
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(root.left > left && root.right > right).tap do
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left = root.left
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right = root.right
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end
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end
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end
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# Rebuilds the left & rights if unset or invalid.
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# Also very useful for converting from acts_as_tree.
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def rebuild!(validate_nodes = true)
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# default_scope with order may break database queries so we do all operation without scope
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unscoped do
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# Don't rebuild a valid tree.
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return true if valid?
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scope = lambda{|node|}
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if acts_as_nested_set_options[:scope]
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scope = lambda{|node|
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scope_column_names.inject(""){|str, column_name|
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str << "AND #{connection.quote_column_name(column_name)} = #{connection.quote(node.send(column_name.to_sym))} "
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}
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}
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end
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indices = {}
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set_left_and_rights = lambda do |node|
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# set left
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node[left_column_name] = indices[scope.call(node)] += 1
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# find
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where(["#{quoted_parent_column_full_name} = ? #{scope.call(node)}", node]).order("#{quoted_left_column_full_name}, #{quoted_right_column_full_name}, id").each{|n| set_left_and_rights.call(n) }
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# set right
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node[right_column_name] = indices[scope.call(node)] += 1
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node.save!(:validate => validate_nodes)
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end
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# Find root node(s)
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root_nodes = where("#{quoted_parent_column_full_name} IS NULL").order("#{quoted_left_column_full_name}, #{quoted_right_column_full_name}, id").each do |root_node|
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# setup index for this scope
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indices[scope.call(root_node)] ||= 0
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set_left_and_rights.call(root_node)
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end
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end
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end
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# Iterates over tree elements and determines the current level in the tree.
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# Only accepts default ordering, odering by an other column than lft
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# does not work. This method is much more efficent than calling level
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# because it doesn't require any additional database queries.
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#
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# Example:
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# Category.each_with_level(Category.root.self_and_descendants) do |o, level|
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#
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def each_with_level(objects)
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path = [nil]
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objects.each do |o|
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if o.parent_id != path.last
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# we are on a new level, did we descend or ascend?
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if path.include?(o.parent_id)
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# remove wrong wrong tailing paths elements
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path.pop while path.last != o.parent_id
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else
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path << o.parent_id
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end
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end
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yield(o, path.length - 1)
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end
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end
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# Same as each_with_level - Accepts a string as a second argument to sort the list
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# Example:
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# Category.each_with_level(Category.root.self_and_descendants, :sort_by_this_column) do |o, level|
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def sorted_each_with_level(objects, order)
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path = [nil]
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children = []
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objects.each do |o|
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children << o if o.leaf?
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if o.parent_id != path.last
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if !children.empty? && !o.leaf?
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children.sort_by! &order
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children.each { |c| yield(c, path.length-1) }
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children = []
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end
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# we are on a new level, did we decent or ascent?
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if path.include?(o.parent_id)
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# remove wrong wrong tailing paths elements
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path.pop while path.last != o.parent_id
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else
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path << o.parent_id
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end
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end
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yield(o,path.length-1) if !o.leaf?
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end
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if !children.empty?
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children.sort_by! &order
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children.each { |c| yield(c, path.length-1) }
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end
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end
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def associate_parents(objects)
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if objects.all?{|o| o.respond_to?(:association)}
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id_indexed = objects.index_by(&:id)
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objects.each do |object|
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if !(association = object.association(:parent)).loaded? && (parent = id_indexed[object.parent_id])
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association.target = parent
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association.set_inverse_instance(parent)
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end
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end
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else
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objects
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end
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end
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end
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# Any instance method that returns a collection makes use of Rails 2.1's named_scope (which is bundled for Rails 2.0), so it can be treated as a finder.
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#
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# category.self_and_descendants.count
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# category.ancestors.find(:all, :conditions => "name like '%foo%'")
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# Value of the parent column
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def parent_id
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self[parent_column_name]
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end
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# Value of the left column
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def left
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self[left_column_name]
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end
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# Value of the right column
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def right
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self[right_column_name]
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end
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# Returns true if this is a root node.
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def root?
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parent_id.nil?
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end
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# Returns true if this is the end of a branch.
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def leaf?
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persisted? && right.to_i - left.to_i == 1
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end
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# Returns true is this is a child node
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def child?
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!root?
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end
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# Returns root
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def root
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if persisted?
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self_and_ancestors.where(parent_column_name => nil).first
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else
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if parent_id && current_parent = nested_set_scope.find(parent_id)
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current_parent.root
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else
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self
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end
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end
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end
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# Returns the array of all parents and self
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def self_and_ancestors
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nested_set_scope.where([
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"#{quoted_left_column_full_name} <= ? AND #{quoted_right_column_full_name} >= ?", left, right
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])
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end
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# Returns an array of all parents
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def ancestors
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without_self self_and_ancestors
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end
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# Returns the array of all children of the parent, including self
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def self_and_siblings
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nested_set_scope.where(parent_column_name => parent_id)
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end
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# Returns the array of all children of the parent, except self
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def siblings
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without_self self_and_siblings
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end
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# Returns a set of all of its nested children which do not have children
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def leaves
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descendants.where("#{quoted_right_column_full_name} - #{quoted_left_column_full_name} = 1")
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end
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# Returns the level of this object in the tree
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# root level is 0
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def level
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parent_id.nil? ? 0 : compute_level
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end
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# Returns a set of itself and all of its nested children
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def self_and_descendants
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nested_set_scope.where([
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"#{quoted_left_column_full_name} >= ? AND #{quoted_left_column_full_name} < ?", left, right
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# using _left_ for both sides here lets us benefit from an index on that column if one exists
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])
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end
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# Returns a set of all of its children and nested children
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def descendants
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without_self self_and_descendants
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end
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def is_descendant_of?(other)
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other.left < self.left && self.left < other.right && same_scope?(other)
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end
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def is_or_is_descendant_of?(other)
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other.left <= self.left && self.left < other.right && same_scope?(other)
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end
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def is_ancestor_of?(other)
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self.left < other.left && other.left < self.right && same_scope?(other)
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end
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def is_or_is_ancestor_of?(other)
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self.left <= other.left && other.left < self.right && same_scope?(other)
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end
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# Check if other model is in the same scope
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def same_scope?(other)
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Array(acts_as_nested_set_options[:scope]).all? do |attr|
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self.send(attr) == other.send(attr)
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end
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end
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# Find the first sibling to the left
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def left_sibling
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siblings.where(["#{quoted_left_column_full_name} < ?", left]).
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order("#{quoted_left_column_full_name} DESC").last
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end
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# Find the first sibling to the right
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def right_sibling
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siblings.where(["#{quoted_left_column_full_name} > ?", left]).first
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end
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# Shorthand method for finding the left sibling and moving to the left of it.
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def move_left
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move_to_left_of left_sibling
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end
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# Shorthand method for finding the right sibling and moving to the right of it.
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def move_right
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move_to_right_of right_sibling
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end
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# Move the node to the left of another node (you can pass id only)
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def move_to_left_of(node)
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move_to node, :left
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end
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# Move the node to the left of another node (you can pass id only)
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def move_to_right_of(node)
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move_to node, :right
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end
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# Move the node to the child of another node (you can pass id only)
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def move_to_child_of(node)
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move_to node, :child
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end
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# Move the node to the child of another node with specify index (you can pass id only)
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def move_to_child_with_index(node, index)
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if node.children.empty?
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move_to_child_of(node)
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elsif node.children.count == index
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move_to_right_of(node.children.last)
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else
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move_to_left_of(node.children[index])
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end
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end
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# Move the node to root nodes
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def move_to_root
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move_to nil, :root
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end
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# Order children in a nested set by an attribute
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# Can order by any attribute class that uses the Comparable mixin, for example a string or integer
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# Usage example when sorting categories alphabetically: @new_category.move_to_ordered_child_of(@root, "name")
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def move_to_ordered_child_of(parent, order_attribute, ascending = true)
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self.move_to_root and return unless parent
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left = nil # This is needed, at least for the tests.
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parent.children.each do |n| # Find the node immediately to the left of this node.
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if ascending
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left = n if n.send(order_attribute) < self.send(order_attribute)
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else
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left = n if n.send(order_attribute) > self.send(order_attribute)
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end
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end
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self.move_to_child_of(parent)
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return unless parent.children.count > 1 # Only need to order if there are multiple children.
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if left # Self has a left neighbor.
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self.move_to_right_of(left)
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else # Self is the left most node.
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self.move_to_left_of(parent.children[0])
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end
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end
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def move_possible?(target)
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self != target && # Can't target self
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same_scope?(target) && # can't be in different scopes
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# !(left..right).include?(target.left..target.right) # this needs tested more
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# detect impossible move
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!((left <= target.left && right >= target.left) or (left <= target.right && right >= target.right))
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end
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def to_text
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self_and_descendants.map do |node|
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"#{'*'*(node.level+1)} #{node.id} #{node.to_s} (#{node.parent_id}, #{node.left}, #{node.right})"
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end.join("\n")
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end
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protected
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def compute_level
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node, nesting = self, 0
|
|
while (association = node.association(:parent)).loaded? && association.target
|
|
nesting += 1
|
|
node = node.parent
|
|
end if node.respond_to? :association
|
|
node == self ? ancestors.count : node.level + nesting
|
|
end
|
|
|
|
def without_self(scope)
|
|
scope.where(["#{self.class.quoted_table_name}.#{self.class.primary_key} != ?", self])
|
|
end
|
|
|
|
# All nested set queries should use this nested_set_scope, which performs finds on
|
|
# the base ActiveRecord class, using the :scope declared in the acts_as_nested_set
|
|
# declaration.
|
|
def nested_set_scope(options = {})
|
|
options = {:order => quoted_left_column_full_name}.merge(options)
|
|
scopes = Array(acts_as_nested_set_options[:scope])
|
|
options[:conditions] = scopes.inject({}) do |conditions,attr|
|
|
conditions.merge attr => self[attr]
|
|
end unless scopes.empty?
|
|
self.class.base_class.unscoped.scoped options
|
|
end
|
|
|
|
def store_new_parent
|
|
@move_to_new_parent_id = send("#{parent_column_name}_changed?") ? parent_id : false
|
|
true # force callback to return true
|
|
end
|
|
|
|
def move_to_new_parent
|
|
if @move_to_new_parent_id.nil?
|
|
move_to_root
|
|
elsif @move_to_new_parent_id
|
|
move_to_child_of(@move_to_new_parent_id)
|
|
end
|
|
end
|
|
|
|
def set_depth!
|
|
if nested_set_scope.column_names.map(&:to_s).include?(depth_column_name.to_s)
|
|
in_tenacious_transaction do
|
|
reload
|
|
|
|
nested_set_scope.where(:id => id).update_all(["#{quoted_depth_column_name} = ?", level])
|
|
end
|
|
self[depth_column_name.to_sym] = self.level
|
|
end
|
|
end
|
|
|
|
def right_most_bound
|
|
right_most_node =
|
|
self.class.base_class.unscoped.
|
|
order("#{quoted_right_column_full_name} desc").limit(1).lock(true).first
|
|
right_most_node ? (right_most_node[right_column_name] || 0) : 0
|
|
end
|
|
|
|
# on creation, set automatically lft and rgt to the end of the tree
|
|
def set_default_left_and_right
|
|
# adds the new node to the right of all existing nodes
|
|
self[left_column_name] = right_most_bound + 1
|
|
self[right_column_name] = right_most_bound + 2
|
|
end
|
|
|
|
def in_tenacious_transaction(&block)
|
|
retry_count = 0
|
|
begin
|
|
transaction(&block)
|
|
rescue ActiveRecord::StatementInvalid => error
|
|
raise unless connection.open_transactions.zero?
|
|
raise unless error.message =~ /Deadlock found when trying to get lock|Lock wait timeout exceeded/
|
|
raise unless retry_count < 10
|
|
retry_count += 1
|
|
logger.info "Deadlock detected on retry #{retry_count}, restarting transaction"
|
|
sleep(rand(retry_count)*0.1) # Aloha protocol
|
|
retry
|
|
end
|
|
end
|
|
|
|
# Prunes a branch off of the tree, shifting all of the elements on the right
|
|
# back to the left so the counts still work.
|
|
def destroy_descendants
|
|
return if right.nil? || left.nil? || skip_before_destroy
|
|
|
|
in_tenacious_transaction do
|
|
reload_nested_set
|
|
# select the rows in the model that extend past the deletion point and apply a lock
|
|
nested_set_scope.where(["#{quoted_left_column_full_name} >= ?", left]).
|
|
select(id).lock(true)
|
|
|
|
if acts_as_nested_set_options[:dependent] == :destroy
|
|
descendants.each do |model|
|
|
model.skip_before_destroy = true
|
|
model.destroy
|
|
end
|
|
else
|
|
nested_set_scope.where(["#{quoted_left_column_name} > ? AND #{quoted_right_column_name} < ?", left, right]).
|
|
delete_all
|
|
end
|
|
|
|
# update lefts and rights for remaining nodes
|
|
diff = right - left + 1
|
|
nested_set_scope.where(["#{quoted_left_column_full_name} > ?", right]).update_all(
|
|
["#{quoted_left_column_name} = (#{quoted_left_column_name} - ?)", diff]
|
|
)
|
|
|
|
nested_set_scope.where(["#{quoted_right_column_full_name} > ?", right]).update_all(
|
|
["#{quoted_right_column_name} = (#{quoted_right_column_name} - ?)", diff]
|
|
)
|
|
|
|
# Don't allow multiple calls to destroy to corrupt the set
|
|
self.skip_before_destroy = true
|
|
end
|
|
end
|
|
|
|
# reload left, right, and parent
|
|
def reload_nested_set
|
|
reload(
|
|
:select => "#{quoted_left_column_full_name}, #{quoted_right_column_full_name}, #{quoted_parent_column_full_name}",
|
|
:lock => true
|
|
)
|
|
end
|
|
|
|
def move_to(target, position)
|
|
raise ActiveRecord::ActiveRecordError, "You cannot move a new node" if self.new_record?
|
|
run_callbacks :move do
|
|
in_tenacious_transaction do
|
|
if target.is_a? self.class.base_class
|
|
target.reload_nested_set
|
|
elsif position != :root
|
|
# load object if node is not an object
|
|
target = nested_set_scope.find(target)
|
|
end
|
|
self.reload_nested_set
|
|
|
|
unless position == :root || move_possible?(target)
|
|
raise ActiveRecord::ActiveRecordError, "Impossible move, target node cannot be inside moved tree."
|
|
end
|
|
|
|
bound = case position
|
|
when :child; target[right_column_name]
|
|
when :left; target[left_column_name]
|
|
when :right; target[right_column_name] + 1
|
|
when :root; 1
|
|
else raise ActiveRecord::ActiveRecordError, "Position should be :child, :left, :right or :root ('#{position}' received)."
|
|
end
|
|
|
|
if bound > self[right_column_name]
|
|
bound = bound - 1
|
|
other_bound = self[right_column_name] + 1
|
|
else
|
|
other_bound = self[left_column_name] - 1
|
|
end
|
|
|
|
# there would be no change
|
|
return if bound == self[right_column_name] || bound == self[left_column_name]
|
|
|
|
# we have defined the boundaries of two non-overlapping intervals,
|
|
# so sorting puts both the intervals and their boundaries in order
|
|
a, b, c, d = [self[left_column_name], self[right_column_name], bound, other_bound].sort
|
|
|
|
# select the rows in the model between a and d, and apply a lock
|
|
self.class.base_class.select('id').lock(true).where(
|
|
["#{quoted_left_column_full_name} >= :a and #{quoted_right_column_full_name} <= :d", {:a => a, :d => d}]
|
|
)
|
|
|
|
new_parent = case position
|
|
when :child; target.id
|
|
when :root; nil
|
|
else target[parent_column_name]
|
|
end
|
|
|
|
where_statement = ["not (#{quoted_left_column_name} = CASE " +
|
|
"WHEN #{quoted_left_column_name} BETWEEN :a AND :b " +
|
|
"THEN #{quoted_left_column_name} + :d - :b " +
|
|
"WHEN #{quoted_left_column_name} BETWEEN :c AND :d " +
|
|
"THEN #{quoted_left_column_name} + :a - :c " +
|
|
"ELSE #{quoted_left_column_name} END AND " +
|
|
"#{quoted_right_column_name} = CASE " +
|
|
"WHEN #{quoted_right_column_name} BETWEEN :a AND :b " +
|
|
"THEN #{quoted_right_column_name} + :d - :b " +
|
|
"WHEN #{quoted_right_column_name} BETWEEN :c AND :d " +
|
|
"THEN #{quoted_right_column_name} + :a - :c " +
|
|
"ELSE #{quoted_right_column_name} END AND " +
|
|
"#{quoted_parent_column_name} = CASE " +
|
|
"WHEN #{self.class.base_class.primary_key} = :id THEN :new_parent " +
|
|
"ELSE #{quoted_parent_column_name} END)" ,
|
|
{:a => a, :b => b, :c => c, :d => d, :id => self.id, :new_parent => new_parent} ]
|
|
|
|
|
|
|
|
|
|
self.nested_set_scope.where(*where_statement).update_all([
|
|
"#{quoted_left_column_name} = CASE " +
|
|
"WHEN #{quoted_left_column_name} BETWEEN :a AND :b " +
|
|
"THEN #{quoted_left_column_name} + :d - :b " +
|
|
"WHEN #{quoted_left_column_name} BETWEEN :c AND :d " +
|
|
"THEN #{quoted_left_column_name} + :a - :c " +
|
|
"ELSE #{quoted_left_column_name} END, " +
|
|
"#{quoted_right_column_name} = CASE " +
|
|
"WHEN #{quoted_right_column_name} BETWEEN :a AND :b " +
|
|
"THEN #{quoted_right_column_name} + :d - :b " +
|
|
"WHEN #{quoted_right_column_name} BETWEEN :c AND :d " +
|
|
"THEN #{quoted_right_column_name} + :a - :c " +
|
|
"ELSE #{quoted_right_column_name} END, " +
|
|
"#{quoted_parent_column_name} = CASE " +
|
|
"WHEN #{self.class.base_class.primary_key} = :id THEN :new_parent " +
|
|
"ELSE #{quoted_parent_column_name} END",
|
|
{:a => a, :b => b, :c => c, :d => d, :id => self.id, :new_parent => new_parent}
|
|
])
|
|
end
|
|
target.reload_nested_set if target
|
|
self.set_depth!
|
|
self.descendants.each(&:save)
|
|
self.reload_nested_set
|
|
end
|
|
end
|
|
|
|
end
|
|
|
|
# Mixed into both classes and instances to provide easy access to the column names
|
|
module Columns
|
|
def left_column_name
|
|
acts_as_nested_set_options[:left_column]
|
|
end
|
|
|
|
def right_column_name
|
|
acts_as_nested_set_options[:right_column]
|
|
end
|
|
|
|
def depth_column_name
|
|
acts_as_nested_set_options[:depth_column]
|
|
end
|
|
|
|
def parent_column_name
|
|
acts_as_nested_set_options[:parent_column]
|
|
end
|
|
|
|
def order_column
|
|
acts_as_nested_set_options[:order_column] || left_column_name
|
|
end
|
|
|
|
def scope_column_names
|
|
Array(acts_as_nested_set_options[:scope])
|
|
end
|
|
|
|
def quoted_left_column_name
|
|
connection.quote_column_name(left_column_name)
|
|
end
|
|
|
|
def quoted_right_column_name
|
|
connection.quote_column_name(right_column_name)
|
|
end
|
|
|
|
def quoted_depth_column_name
|
|
connection.quote_column_name(depth_column_name)
|
|
end
|
|
|
|
def quoted_parent_column_name
|
|
connection.quote_column_name(parent_column_name)
|
|
end
|
|
|
|
def quoted_scope_column_names
|
|
scope_column_names.collect {|column_name| connection.quote_column_name(column_name) }
|
|
end
|
|
|
|
def quoted_left_column_full_name
|
|
"#{quoted_table_name}.#{quoted_left_column_name}"
|
|
end
|
|
|
|
def quoted_right_column_full_name
|
|
"#{quoted_table_name}.#{quoted_right_column_name}"
|
|
end
|
|
|
|
def quoted_parent_column_full_name
|
|
"#{quoted_table_name}.#{quoted_parent_column_name}"
|
|
end
|
|
end
|
|
|
|
end
|
|
end
|
|
end
|