Allow UUIDs and other types of non-integer primary keys

closure_tree.gemspec

@@ -25,6 +25,7 @@ Gem::Specification.new do |gem|
   gem.add_development_dependency 'mysql2'
   gem.add_development_dependency 'pg'
   gem.add_development_dependency 'sqlite3'
+  gem.add_development_dependency 'uuidtools'
   gem.add_development_dependency 'strong_parameters'
   # TODO: gem 'activerecord-jdbcsqlite3-adapter', :platform => :jruby
 end

lib/closure_tree/acts_as_tree.rb

@@ -237,7 +237,7 @@ def find_all_by_generation(generation_level)
         INNER JOIN (
           SELECT descendant_id
           FROM #{quoted_hierarchy_table_name}
-          WHERE ancestor_id = #{self.id}
+          WHERE ancestor_id = #{ct_quote(self.id)}
           GROUP BY 1
           HAVING MAX(#{quoted_hierarchy_table_name}.generations) = #{generation_level.to_i}
         ) AS descendants ON (#{quoted_table_name}.#{ct_base_class.primary_key} = descendants.descendant_id)
@@ -290,9 +290,9 @@ def rebuild!
         connection.execute <<-SQL
           INSERT INTO #{quoted_hierarchy_table_name}
             (ancestor_id, descendant_id, generations)
-          SELECT x.ancestor_id, #{id}, x.generations + 1
+          SELECT x.ancestor_id, #{ct_quote(id)}, x.generations + 1
           FROM #{quoted_hierarchy_table_name} x
-          WHERE x.descendant_id = #{self.ct_parent_id}
+          WHERE x.descendant_id = #{ct_quote(self.ct_parent_id)}
         SQL
       end
       children.each { |c| c.rebuild! }
@@ -316,9 +316,9 @@ def delete_hierarchy_references
           SELECT DISTINCT descendant_id
           FROM ( SELECT descendant_id
             FROM #{quoted_hierarchy_table_name}
-            WHERE ancestor_id = #{id}
+            WHERE ancestor_id = #{ct_quote(id)}
           ) AS x )
-          OR descendant_id = #{id}
+          OR descendant_id = #{ct_quote(id)}
       SQL
     end
 
@@ -334,6 +334,10 @@ def ids_from(scope)
       end
     end
 
+    def ct_quote(id)
+      self.class.connection.quote(id)
+    end
+
     # TODO: _parent_id will be removed in the next major version
     alias :_parent_id :ct_parent_id
 

spec/db/schema.rb

@@ -11,6 +11,22 @@ def force_add_index(table_name, columns, options = {})
 
 ActiveRecord::Schema.define(:version => 0) do
 
+  create_table "nodes", :id => false do |t|
+    t.string "id"
+    t.string "name"
+    t.string "parent_id"
+    t.datetime "created_at"
+    t.datetime "updated_at"
+  end
+
+  force_add_index "nodes", [:id], :name => "node_id", :unique => true
+
+  create_table "node_hierarchies", :id => false, :force => true do |t|
+    t.string "ancestor_id", :null => false
+    t.string "descendant_id", :null => false
+    t.integer "generations", :null => false
+  end
+
   create_table "tags", :force => true do |t|
     t.string "name"
     t.string "title"

spec/node_spec.rb

@@ -0,0 +1,148 @@
+require 'spec_helper'
+
+shared_examples_for Node do
+
+  it "has correct accessible_attributes" do
+    Node.accessible_attributes.to_a.should =~ %w(parent name)
+  end
+
+  describe "empty db" do
+
+    def nuke_db
+      NodeHierarchy.delete_all
+      Node.delete_all
+    end
+
+    before :each do
+      nuke_db
+    end
+
+    context "empty db" do
+      it "should return no entities" do
+        Node.roots.should be_empty
+        Node.leaves.should be_empty
+      end
+    end
+
+    context "1 node db" do
+      it "should return the only entity as a root and leaf" do
+        a = Node.create!(:name => "a")
+        Node.roots.should == [a]
+        Node.leaves.should == [a]
+      end
+    end
+
+    context "2 node db" do
+      it "should return a simple root and leaf" do
+        root = Node.create!(:name => "root")
+        leaf = root.add_child(Node.create!(:name => "leaf"))
+        Node.roots.should == [root]
+        Node.leaves.should == [leaf]
+      end
+    end
+
+    context "3 node collection.create db" do
+      before :each do
+        @root = Node.create! :name => "root"
+        @mid = @root.children.create! :name => "mid"
+        @leaf = @mid.children.create! :name => "leaf"
+      end
+
+      it "should create all nodes" do
+        Node.all.should =~ [@root, @mid, @leaf]
+      end
+
+      it "should return a root and leaf without middle node" do
+        Node.roots.should == [@root]
+        Node.leaves.should == [@leaf]
+      end
+
+      it "should delete leaves" do
+        Node.leaves.destroy_all
+        Node.roots.should == [@root] # untouched
+        Node.leaves.should == [@mid]
+      end
+
+      it "should delete everything if you delete the roots" do
+        Node.roots.destroy_all
+        Node.all.should be_empty
+        Node.roots.should be_empty
+        Node.leaves.should be_empty
+      end
+    end
+
+    context "3 node explicit_create db" do
+      before :each do
+        @root = Node.create!(:name => "root")
+        @mid = @root.add_child(Node.create!(:name => "mid"))
+        @leaf = @mid.add_child(Node.create!(:name => "leaf"))
+      end
+
+      it "should create all nodes" do
+        Node.all.should =~ [@root, @mid, @leaf]
+      end
+
+      it "should return a root and leaf without middle node" do
+        Node.roots.should == [@root]
+        Node.leaves.should == [@leaf]
+      end
+
+      it "should prevent parental loops from torso" do
+        @mid.children << @root
+        @root.valid?.should be_false
+        @mid.reload.children.should == [@leaf]
+      end
+
+      it "should prevent parental loops from toes" do
+        @leaf.children << @root
+        @root.valid?.should be_false
+        @leaf.reload.children.should be_empty
+      end
+
+      it "should support re-parenting" do
+        @root.children << @leaf
+        Node.leaves.should =~ [@leaf, @mid]
+      end
+
+      it "cleans up hierarchy references for leaves" do
+        @leaf.destroy
+        NodeHierarchy.find_all_by_ancestor_id(@leaf.id).should be_empty
+        NodeHierarchy.find_all_by_descendant_id(@leaf.id).should be_empty
+      end
+
+      it "cleans up hierarchy references" do
+        @mid.destroy
+        NodeHierarchy.find_all_by_ancestor_id(@mid.id).should be_empty
+        NodeHierarchy.find_all_by_descendant_id(@mid.id).should be_empty
+        @root.reload.should be_root
+        root_hiers = @root.ancestor_hierarchies.to_a
+        root_hiers.size.should == 1
+        NodeHierarchy.find_all_by_ancestor_id(@root.id).should == root_hiers
+        NodeHierarchy.find_all_by_descendant_id(@root.id).should == root_hiers
+      end
+    end
+
+    it "performs as the readme says it does" do
+      grandparent = Node.create(:name => 'Grandparent')
+      parent = grandparent.children.create(:name => 'Parent')
+      child1 = Node.create(:name => 'First Child', :parent => parent)
+      child2 = Node.new(:name => 'Second Child')
+      parent.children << child2
+      child3 = Node.new(:name => 'Third Child')
+      parent.add_child child3
+      grandparent.self_and_descendants.collect(&:name).should ==
+        ["Grandparent", "Parent", "First Child", "Second Child", "Third Child"]
+      child1.ancestry_path.should ==
+        ["Grandparent", "Parent", "First Child"]
+      child3.ancestry_path.should ==
+        ["Grandparent", "Parent", "Third Child"]
+      d = Node.find_or_create_by_path %w(a b c d)
+      h = Node.find_or_create_by_path %w(e f g h)
+      e = h.root
+      d.add_child(e) # "d.children << e" would work too, of course
+      h.ancestry_path.should == %w(a b c d e f g h)
+    end
+
+  end
+
+end

spec/support/models.rb

@@ -1,3 +1,15 @@
+require 'uuidtools'
+
+class Node < ActiveRecord::Base
+  acts_as_tree :dependent => :destroy
+  before_create :generate_uuid
+  attr_accessible :name
+
+  def generate_uuid
+    self.id = UUIDTools::UUID.random_create.to_s
+  end
+end
+
 class Tag < ActiveRecord::Base
   acts_as_tree :dependent => :destroy, :order => "name"
   before_destroy :add_destroyed_tag
@@ -60,4 +72,4 @@ class DirectoryLabel < Label
 
 class CuisineType < ActiveRecord::Base
   acts_as_tree
-end
+end