[Fix #51524] Fix strict_loading violations ignored when using pluck

activerecord/CHANGELOG.md

@@ -1,3 +1,7 @@
+*   Fix `strict_loading` violations ignored when using `pluck`
+
+    *Johnson Chan*
+
 *   Strict loading using `:n_plus_one_only` does not eagerly load child associations.
 
     With this change, child associations are no longer eagerly loaded, to

activerecord/lib/active_record/associations/association.rb

@@ -210,6 +210,18 @@ def create!(attributes = nil, &block)
         _create_record(attributes, true, &block)
       end
 
+      def violates_strict_loading?
+        return unless find_target?
+
+        return if @skip_strict_loading
+
+        return unless owner.validation_context.nil?
+
+        return reflection.strict_loading? if reflection.options.key?(:strict_loading)
+
+        owner.strict_loading? && !owner.strict_loading_n_plus_one_only?
+      end
+
       private
         # Reader and writer methods call this so that consistent errors are presented
         # when the association target class does not exist.
@@ -251,16 +263,6 @@ def skip_strict_loading(&block)
           @skip_strict_loading = skip_strict_loading_was
         end
 
-        def violates_strict_loading?
-          return if @skip_strict_loading
-
-          return unless owner.validation_context.nil?
-
-          return reflection.strict_loading? if reflection.options.key?(:strict_loading)
-
-          owner.strict_loading? && !owner.strict_loading_n_plus_one_only?
-        end
-
         # The scope for this association.
         #
         # Note that the association_scope is merged into the target_scope only when the

activerecord/lib/active_record/relation/calculations.rb

@@ -285,6 +285,10 @@ def calculate(operation, column_name)
     #
     # See also #ids.
     def pluck(*column_names)
+      if respond_to?(:proxy_association) && proxy_association.violates_strict_loading?
+        Base.strict_loading_violation!(owner: proxy_association.owner.class, reflection: proxy_association.reflection)
+      end
+
       if @none
         if @async
           return Promise::Complete.new([])

activerecord/test/cases/strict_loading_test.rb

@@ -317,6 +317,25 @@ def test_strict_loading_with_has_one_through_does_not_prevent_creation_of_associ
     end
   end
 
+  def test_on_lazy_loading_and_strict_loading_with_pluck
+    with_strict_loading_by_default(Developer) do
+      dev = Developer.first
+
+      assert_raises ActiveRecord::StrictLoadingViolationError do
+        dev.audit_logs.pluck(:id)
+      end
+    end
+  end
+
+  def test_preload_audit_logs_are_strict_loading_with_pluck
+    with_strict_loading_by_default(Developer) do
+      dev = Developer.preload(:audit_logs).first
+
+      assert_nothing_raised do
+        dev.audit_logs.pluck(:id)
+      end
+    end
+  end
 
   def test_preload_audit_logs_are_strict_loading_because_parent_is_strict_loading
     developer = Developer.first