serialized_property setter의 불필요한 dirty marking 수정

lib/coaster/serialized_properties.rb

@@ -27,15 +27,26 @@ def _write_sprop_value(key, value, apply_setter: true)
             setting = self.class.serialized_property_setting(key)
             return unless setting
             col = setting[:column]
-            send("#{col}_will_change!")
             hsh = send(col)
-            if value.nil?
+            old_value = hsh[key.to_s]
+
+            new_value = if value.nil?
+              nil
+            else
+              apply_setter && setting[:setter] ? setting[:setter].call(value) : value
+            end
+
+            # Skip dirty marking if value hasn't changed
+            return old_value if old_value == new_value
+
+            send("#{col}_will_change!")
+
+            if new_value.nil?
               hsh.delete(key.to_s)
             else
-              value = setting[:setter].call(value) if apply_setter && setting[:setter]
-              hsh[key.to_s] = value
+              hsh[key.to_s] = new_value
             end
-            value
+            new_value
           end
 
           def write_attribute(attr_name, value)
@@ -312,15 +323,26 @@ def _define_serialized_property(serialize_column, key, getter: nil, setter: nil,
       if is_active_record
         define_method "#{key}_without_callback=".to_sym do |val|
           col = serialize_column
-          send("#{col}_will_change!")
           hsh = send(col)
-          if val.nil?
+          old_value = hsh[key.to_s]
+
+          new_value = if val.nil?
+            nil
+          else
+            setter ? setter.call(val) : val
+          end
+
+          # Skip dirty marking if value hasn't changed
+          return old_value if old_value == new_value
+
+          send("#{col}_will_change!")
+
+          if new_value.nil?
             hsh.delete(key.to_s)
           else
-            val = setter.call(val) if setter
-            hsh[key.to_s] = val
+            hsh[key.to_s] = new_value
           end
-          val
+          new_value
         end
       else
         define_method "#{key}_without_callback=".to_sym do |val|

test/test_serialized_property.rb

@@ -372,5 +372,113 @@ def test_nil_value_with_getter_setter
       assert_nil student.encrypted_value
       assert_nil student.data['encrypted_value']
     end
+
+    # Tests for dirty tracking optimization (skip dirty marking when value unchanged)
+    def test_same_value_setter_does_not_mark_dirty
+      user = User.create(name: 'test_same_value')
+      user.simple = 'initial_value'
+      user.save!
+
+      # Reload to clear dirty state
+      user.reload
+      assert_equal false, user.changed?
+
+      # Set same value - should NOT mark dirty
+      user.simple = 'initial_value'
+      assert_equal false, user.simple_changed?, 'Setting same value should not mark property as changed'
+      assert_equal false, user.changed?, 'Setting same value should not mark record as changed'
+    end
+
+    def test_different_value_setter_marks_dirty
+      user = User.create(name: 'test_different_value')
+      user.simple = 'initial_value'
+      user.save!
+      user.reload
+
+      # Set different value - should mark dirty
+      user.simple = 'new_value'
+      assert_equal true, user.simple_changed?, 'Setting different value should mark property as changed'
+      assert_equal true, user.changed?, 'Setting different value should mark record as changed'
+      assert_equal ['initial_value', 'new_value'], user.simple_change
+    end
+
+    def test_nil_to_value_marks_dirty
+      user = User.create(name: 'test_nil_to_value')
+      user.save!
+      user.reload
+
+      assert_nil user.simple
+      user.simple = 'some_value'
+      assert_equal true, user.simple_changed?
+      assert_equal [nil, 'some_value'], user.simple_change
+    end
+
+    def test_value_to_nil_marks_dirty
+      user = User.create(name: 'test_value_to_nil')
+      user.simple = 'some_value'
+      user.save!
+      user.reload
+
+      user.simple = nil
+      assert_equal true, user.simple_changed?
+      assert_equal ['some_value', nil], user.simple_change
+    end
+
+    def test_nil_to_nil_does_not_mark_dirty
+      user = User.create(name: 'test_nil_to_nil')
+      user.save!
+      user.reload
+
+      assert_nil user.simple
+      user.simple = nil
+      assert_equal false, user.simple_changed?, 'Setting nil to nil should not mark as changed'
+      assert_equal false, user.changed?
+    end
+
+    def test_same_value_via_write_attribute_does_not_mark_dirty
+      user = User.create(name: 'test_write_attr_same')
+      user.write_attribute(:simple, 'initial')
+      user.save!
+      user.reload
+
+      user.write_attribute(:simple, 'initial')
+      assert_equal false, user.simple_changed?
+      assert_equal false, user.changed?
+    end
+
+    def test_same_value_via_bracket_accessor_does_not_mark_dirty
+      user = User.create(name: 'test_bracket_same')
+      user[:simple] = 'initial'
+      user.save!
+      user.reload
+
+      user[:simple] = 'initial'
+      assert_equal false, user.simple_changed?
+      assert_equal false, user.changed?
+    end
+
+    def test_same_value_with_setter_proc_does_not_mark_dirty
+      student = Student.create(name: 'test_setter_same')
+      student.uppercase_name = 'hello'  # Stored as 'HELLO'
+      student.save!
+      student.reload
+
+      # Setting same raw input - setter transforms to same value
+      student.uppercase_name = 'hello'
+      assert_equal false, student.uppercase_name_changed?, 'Same value after setter transform should not mark dirty'
+      assert_equal false, student.changed?
+    end
+
+    def test_different_case_with_setter_proc_marks_dirty
+      student = Student.create(name: 'test_setter_diff')
+      student.uppercase_name = 'hello'  # Stored as 'HELLO'
+      student.save!
+      student.reload
+
+      # Setting different value
+      student.uppercase_name = 'world'  # Stored as 'WORLD'
+      assert_equal true, student.uppercase_name_changed?
+      assert_equal ['HELLO', 'WORLD'], student.uppercase_name_change
+    end
   end
 end