Merge pull request #45931 from fatkodima/follow-up-45695

Do not mutate relation when implicitly selecting a primary key in `ActiveRecord.find`

activerecord/lib/active_record/relation/finder_methods.rb

@@ -448,7 +448,6 @@ module ActiveRecord
         ids = ids.flatten.compact.uniq
 
         model_name = @klass.name
-        _select!(table[primary_key]) unless select_values.empty?
 
         case ids.size
         when 0
@@ -481,7 +480,9 @@ module ActiveRecord
       def find_some(ids)
         return find_some_ordered(ids) unless order_values.present?
 
-        result = where(primary_key => ids).to_a
+        relation = where(primary_key => ids)
+        relation = relation.select(table[primary_key]) unless select_values.empty?
+        result = relation.to_a
 
         expected_size =
           if limit_value && ids.size > limit_value
@@ -505,7 +506,9 @@ module ActiveRecord
       def find_some_ordered(ids)
         ids = ids.slice(offset_value || 0, limit_value || ids.size) || []
 
-        result = except(:limit, :offset).where(primary_key => ids).records
+        relation = except(:limit, :offset).where(primary_key => ids)
+        relation = relation.select(table[primary_key]) unless select_values.empty?
+        result = relation.records
 
         if result.size == ids.size
           result.in_order_of(:id, ids.map { |id| @klass.type_for_attribute(primary_key).cast(id) })

activerecord/test/cases/finder_test.rb

@@ -53,9 +53,6 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_with_custom_select_excluding_id
-    topic = Topic.select(:title).find(4)
-    assert_equal 4, topic.id
-
     # Returns ordered by ids array
     topics = Topic.select(:title).find([4, 2, 5])
     assert_equal [4, 2, 5], topics.map(&:id)