Merge pull request rails#48983 from JoeDupuis/fix-regression-on-strict-has-one-through

Fix regression blocking creation of some strict association

Author: byroot

activerecord/lib/active_record/associations/through_association.rb

@@ -81,9 +81,9 @@ def construct_join_attributes(*records)
         # to try to properly support stale-checking for nested associations.
         def stale_state
           if through_reflection.belongs_to?
-            Array(through_reflection.foreign_key).map do |foreign_key_column|
+            Array(through_reflection.foreign_key).filter_map do |foreign_key_column|
               owner[foreign_key_column] && owner[foreign_key_column].to_s
-            end
+            end.presence
           end
         end
 

activerecord/test/cases/strict_loading_test.rb

@@ -284,6 +284,20 @@ def test_strict_loading_with_has_many_through_cascade_down_to_middle_records
     end
   end
 
+  def test_strict_loading_with_has_one_through_does_not_prevent_creation_of_association
+    firm = Firm.new(name: "SuperFirm").tap(&:strict_loading!)
+    computer = Computer.new(extendedWarranty: 1).tap(&:strict_loading!)
+
+    computer.firm = firm
+    computer.developer.name = "Joe"
+    firm.lead_developer = computer.developer
+
+    assert_nothing_raised do
+      computer.save!
+    end
+  end
+
+
   def test_preload_audit_logs_are_strict_loading_because_parent_is_strict_loading
     developer = Developer.first
 

activerecord/test/models/computer.rb

@@ -2,4 +2,5 @@
 
 class Computer < ActiveRecord::Base
   belongs_to :developer, foreign_key: "developer"
+  has_one :firm, through: :developer
 end

activerecord/test/models/developer.rb

@@ -38,6 +38,7 @@ def find_most_recent
   accepts_nested_attributes_for :projects
 
   has_and_belongs_to_many :shared_computers, class_name: "Computer"
+  has_many :computers, foreign_key: :developer
 
   has_and_belongs_to_many :projects_extended_by_name,
       -> { extending(ProjectsAssociationExtension) },