Included associations: go deep.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4776 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

7 files changed, 66 insertions, 4 deletions

diff --git a/activerecord/test/associations_cascaded_eager_loading_test.rb b/activerecord/test/associations_cascaded_eager_loading_test.rb
index 20df8cd30e..863af199ce 100644
--- a/activerecord/test/associations_cascaded_eager_loading_test.rb
+++ b/activerecord/test/associations_cascaded_eager_loading_test.rb
@@ -11,7 +11,7 @@ require 'fixtures/topic'
 require 'fixtures/reply'
 
 class CascadedEagerLoadingTest < Test::Unit::TestCase
-  fixtures :authors, :mixins, :companies, :posts, :categorizations, :topics
+  fixtures :authors, :mixins, :companies, :posts, :topics
 
   def test_eager_association_loading_with_cascaded_two_levels
     authors = Author.find(:all, :include=>{:posts=>:comments}, :order=>"authors.id")
@@ -94,7 +94,7 @@ class CascadedEagerLoadingTest < Test::Unit::TestCase
       author.posts.first.very_special_comment
     end
   end
-  
+
   def test_eager_association_loading_of_stis_with_multiple_references
     authors = Author.find(:all, :include => { :posts => { :special_comments => { :post => [ :special_comments, :very_special_comment ] } } }, :order => 'comments.body, very_special_comments_posts.body', :conditions => 'posts.id = 4')
     assert_equal [authors(:david)], authors
@@ -103,9 +103,36 @@ class CascadedEagerLoadingTest < Test::Unit::TestCase
       authors.first.posts.first.special_comments.first.post.very_special_comment
     end
   end
-  
-  def test_eager_association_loading_with_recursive_cascaded_three_levels
+
+  def test_eager_association_loading_with_recursive_cascading_three_levels_has_many
     root_node = RecursivelyCascadedTreeMixin.find(:first, :include=>{:children=>{:children=>:children}}, :order => 'mixins.id')
     assert_equal mixins(:recursively_cascaded_tree_4), assert_no_queries { root_node.children.first.children.first.children.first }
   end
+
+  def test_eager_association_loading_with_recursive_cascading_three_levels_has_one
+    root_node = RecursivelyCascadedTreeMixin.find(:first, :include=>{:first_child=>{:first_child=>:first_child}}, :order => 'mixins.id')
+    assert_equal mixins(:recursively_cascaded_tree_4), assert_no_queries { root_node.first_child.first_child.first_child }
+  end
+
+  def test_eager_association_loading_with_recursive_cascading_three_levels_belongs_to
+    leaf_node = RecursivelyCascadedTreeMixin.find(:first, :include=>{:parent=>{:parent=>:parent}}, :order => 'mixins.id DESC')
+    assert_equal mixins(:recursively_cascaded_tree_1), assert_no_queries { leaf_node.parent.parent.parent }
+  end
+end
+
+
+require 'fixtures/vertex'
+require 'fixtures/edge'
+class CascadedEagerLoadingTest < Test::Unit::TestCase
+  fixtures :edges, :vertices
+
+  def test_eager_association_loading_with_recursive_cascading_four_levels_has_many_through
+    source = Vertex.find(:first, :include=>{:sinks=>{:sinks=>{:sinks=>:sinks}}}, :order => 'vertices.id')
+    assert_equal vertices(:vertex_4), assert_no_queries { source.sinks.first.sinks.first.sinks.first }
+  end
+
+  def test_eager_association_loading_with_recursive_cascading_four_levels_has_and_belongs_to_many
+    sink = Vertex.find(:first, :include=>{:sources=>{:sources=>{:sources=>:sources}}}, :order => 'vertices.id DESC')
+    assert_equal vertices(:vertex_1), assert_no_queries { sink.sources.first.sources.first.sources.first.sources.first }
+  end
 end
diff --git a/activerecord/test/fixtures/db_definitions/schema.rb b/activerecord/test/fixtures/db_definitions/schema.rb
index a5f2c9dc10..f565b74564 100644
--- a/activerecord/test/fixtures/db_definitions/schema.rb
+++ b/activerecord/test/fixtures/db_definitions/schema.rb
@@ -39,4 +39,14 @@ ActiveRecord::Schema.define do
     t.column :author_id, :integer
     t.column :favorite_author_id, :integer
   end
+
+  create_table :vertices, :force => true do |t|
+    t.column :label, :string
+  end
+
+  create_table :edges, :force => true do |t|
+    t.column :source_id, :integer, :null => false
+    t.column :sink_id,   :integer, :null => false
+  end
+  add_index :edges, [:source_id, :sink_id], :unique => true
 end
diff --git a/activerecord/test/fixtures/edge.rb b/activerecord/test/fixtures/edge.rb
new file mode 100644
index 0000000000..55e0c31fcb
--- /dev/null
+++ b/activerecord/test/fixtures/edge.rb
@@ -0,0 +1,5 @@
+# This class models an edge in a directed graph.
+class Edge < ActiveRecord::Base
+  belongs_to :source, :class_name => 'Vertex', :foreign_key => 'source_id'
+  belongs_to :sink,   :class_name => 'Vertex', :foreign_key => 'sink_id'
+end
diff --git a/activerecord/test/fixtures/edges.yml b/activerecord/test/fixtures/edges.yml
new file mode 100644
index 0000000000..c16c70dd2f
--- /dev/null
+++ b/activerecord/test/fixtures/edges.yml
@@ -0,0 +1,6 @@
+<% (1..4).each do |id| %>
+edge_<%= id %>:
+  id: <%= id %>
+  source_id: <%= id %>
+  sink_id: <%= id + 1 %>
+<% end %>
\ No newline at end of file
diff --git a/activerecord/test/fixtures/mixin.rb b/activerecord/test/fixtures/mixin.rb
index afc976f8f1..1f200da62d 100644
--- a/activerecord/test/fixtures/mixin.rb
+++ b/activerecord/test/fixtures/mixin.rb
@@ -12,6 +12,7 @@ end
 
 class RecursivelyCascadedTreeMixin < Mixin
   acts_as_tree :foreign_key => "parent_id"
+  has_one :first_child, :class_name => 'RecursivelyCascadedTreeMixin', :foreign_key => :parent_id
 end
 
 class ListMixin < Mixin
diff --git a/activerecord/test/fixtures/vertex.rb b/activerecord/test/fixtures/vertex.rb
new file mode 100644
index 0000000000..f4c11144de
--- /dev/null
+++ b/activerecord/test/fixtures/vertex.rb
@@ -0,0 +1,9 @@
+# This class models a vertex in a directed graph.
+class Vertex < ActiveRecord::Base
+  has_many :sink_edges, :class_name => 'Edge', :foreign_key => 'source_id'
+  has_many :sinks, :through => :sink_edges, :source => :sink
+
+  has_and_belongs_to_many :sources,
+    :class_name => 'Vertex', :join_table => 'edges',
+    :foreign_key => 'sink_id', :association_foreign_key => 'source_id'
+end
diff --git a/activerecord/test/fixtures/vertices.yml b/activerecord/test/fixtures/vertices.yml
new file mode 100644
index 0000000000..8af0593f75
--- /dev/null
+++ b/activerecord/test/fixtures/vertices.yml
@@ -0,0 +1,4 @@
+<% (1..5).each do |id| %>
+vertex_<%= id %>:
+  id: <%= id %>
+<% end %>
\ No newline at end of file