Fix for has_and_belongs_to_many & has_many_through associations while partial_writes is false

This will fix #19663

Also with this fix, active record does not fire unnecassary update queries while partial_writes is true

1 files changed, 13 insertions, 0 deletions

diff --git a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
index 5c4586da19..cab9dff6ca 100644
--- a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
@@ -982,4 +982,17 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
       Project.first.developers_required_by_default.create!(name: "Sean", salary: 50000)
     end
   end
+
+  def test_has_and_belongs_to_many_while_partial_writes_false
+    begin
+      original_partial_writes = ActiveRecord::Base.partial_writes
+      ActiveRecord::Base.partial_writes = false
+      developer = Developer.new(name: "Mehmet Emin İNAÇ")
+      developer.projects << Project.new(name: "Bounty")
+
+      assert developer.save
+    ensure
+      ActiveRecord::Base.partial_writes = original_partial_writes
+    end
+  end
 end