From 5c89d1689981a31bb7e54f0d23269786d222183c Mon Sep 17 00:00:00 2001
From: Michael Smedberg <msmedberg@zendesk.com>
Date: Fri, 26 Jan 2018 14:17:32 -0800
Subject: [PATCH] :inherit associations should properly scope :through joins

---
 lib/active_record_inherit_assoc.rb |  7 ++++++-
 test/schema.rb                     | 13 +++++++++++++
 test/test_inherit_assoc.rb         | 30 ++++++++++++++++++++++++++++++
 3 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/lib/active_record_inherit_assoc.rb b/lib/active_record_inherit_assoc.rb
index 31c060c..38608bd 100644
--- a/lib/active_record_inherit_assoc.rb
+++ b/lib/active_record_inherit_assoc.rb
@@ -31,7 +31,12 @@ def target_scope
 
   def attribute_inheritance_hash
     return nil unless reflection.options[:inherit]
-    Array(reflection.options[:inherit]).inject({}) { |hash, association| hash[association] = owner.send(association) ; hash }
+    Array(reflection.options[:inherit]).inject({}) do |hash, association|
+      assoc_value = owner.send(association)
+      hash[association] = assoc_value
+      hash["#{through_reflection.table_name}.#{association}"] = assoc_value if reflection.options.key?(:through)
+      hash
+    end
   end
 
   if ActiveRecord::VERSION::MAJOR >= 4
diff --git a/test/schema.rb b/test/schema.rb
index 45cf0aa..2eec1e3 100644
--- a/test/schema.rb
+++ b/test/schema.rb
@@ -25,4 +25,17 @@
     t.integer :account_id
     t.integer :blah_id
   end
+
+  drop_table(:fifths) rescue nil
+  create_table "fifths" do |t|
+    t.integer :main_id
+    t.integer :account_id
+    t.integer :sixth_id
+  end
+
+  drop_table(:sixths) rescue nil
+  create_table "sixths" do |t|
+    t.integer :main_id
+    t.integer :account_id
+  end
 end
diff --git a/test/test_inherit_assoc.rb b/test/test_inherit_assoc.rb
index 770c18b..4db511f 100644
--- a/test/test_inherit_assoc.rb
+++ b/test/test_inherit_assoc.rb
@@ -8,6 +8,8 @@ class Main < ActiveRecord::Base
     if ActiveRecord::VERSION::MAJOR < 4
       has_many :conditional_others, :inherit => :account_id, :conditions => {:val => "foo"}, :class_name => "Other"
     end
+    has_many :fifths, :inherit => :account_id
+    has_many :sixths, :through => :fifths, inherit: :account_id
   end
 
   class Other < ActiveRecord::Base
@@ -22,6 +24,15 @@ class Fourth < ActiveRecord::Base
     belongs_to :main
   end
 
+  class Fifth < ActiveRecord::Base
+    belongs_to :main, inherit: :account_id
+    belongs_to :sixth, inherit: :account_id
+  end
+
+  class Sixth < ActiveRecord::Base
+    belongs_to :main
+  end
+
   describe "Main, with some others, scoped by account_id" do
     before do
       @main = Main.create! :account_id => 1
@@ -96,6 +107,25 @@ def test_has_one_should_set_conditions_on_includes_with_multiple_owners
     assert_equal third_4, mains.last.third
   end
 
+  def test_has_many_through_should_set_conditions_on_join_table
+    main_1 = Main.create! :account_id => 1
+    main_2 = Main.create! :account_id => 1
+
+    sixth_1 = Sixth.create! :main_id => main_1.id, :account_id => 1
+    sixth_2 = Sixth.create! :main_id => main_1.id, :account_id => 1
+    sixth_3 = Sixth.create! :main_id => main_1.id, :account_id => 1
+    sixth_4 = Sixth.create! :main_id => main_1.id, :account_id => 1
+
+    Fifth.create! :main_id => main_1.id, :account_id => 2, :sixth_id => sixth_1.id
+    Fifth.create! :main_id => main_1.id, :account_id => 1, :sixth_id => sixth_2.id
+    Fifth.create! :main_id => main_2.id, :account_id => 2, :sixth_id => sixth_3.id
+    Fifth.create! :main_id => main_2.id, :account_id => 1, :sixth_id => sixth_4.id
+
+    mains = Main.where(id: [main_1.id, main_2.id])
+    assert_equal [sixth_2], mains.first.sixths
+    assert_equal [sixth_4], mains.last.sixths
+  end
+
   def test_has_many_should_set_conditions_on_includes
     main = Main.create! :account_id => 1, :blah_id => 10