1 files changed, 18 insertions, 1 deletions
diff --git a/activerecord/test/cases/associations/has_many_associations_test.rb b/activerecord/test/cases/associations/has_many_associations_test.rb
index 4ca11af791..18548f8516 100644
--- a/activerecord/test/cases/associations/has_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_associations_test.rb
@@ -2350,7 +2350,7 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
 
   test "does not duplicate associations when used with natural primary keys" do
     speedometer = Speedometer.create!(id: "4")
-    speedometer.minivans.create!(minivan_id: "a-van-red" , name: "a van", color: "red")
+    speedometer.minivans.create!(minivan_id: "a-van-red", name: "a van", color: "red")
 
     assert_equal 1, speedometer.minivans.to_a.size, "Only one association should be present:\n#{speedometer.minivans.to_a}"
     assert_equal 1, speedometer.reload.minivans.to_a.size
@@ -2509,6 +2509,15 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_same car, new_bulb.car
   end
 
+  test "reattach to new objects replaces inverse association and foreign key" do
+    bulb = Bulb.create!(car: Car.create!)
+    assert bulb.car_id
+    car = Car.new
+    car.bulbs << bulb
+    assert_equal car, bulb.car
+    assert_nil bulb.car_id
+  end
+
   test "in memory replacement maintains order" do
     first_bulb = Bulb.create!
     second_bulb = Bulb.create!
@@ -2520,6 +2529,14 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal [first_bulb, second_bulb], car.bulbs
   end
 
+  test "association size calculation works with default scoped selects when not previously fetched" do
+    firm = Firm.create!(name: "Firm")
+    5.times { firm.developers_with_select << Developer.create!(name: "Developer") }
+
+    same_firm = Firm.find(firm.id)
+    assert_equal 5, same_firm.developers_with_select.size
+  end
+
   test "prevent double insertion of new object when the parent association loaded in the after save callback" do
     reset_callbacks(:save, Bulb) do
       Bulb.after_save { |record| record.car.bulbs.load }