Warn scoped order and limit are ignored. [#4123 state:resolved]

activerecord/lib/active_record/relation/batches.rb

@@ -50,6 +50,10 @@ def find_each(options = {})
     def find_in_batches(options = {})
       relation = self
 
+       if orders.present? || taken.present?
+         ActiveRecord::Base.logger.warn("Scoped order and limit are ignored, it's forced to be batch order and batch size")
+       end
+
       if (finder_options = options.except(:start, :batch_size)).present?
         raise "You can't specify an order, it's forced to be #{batch_order}" if options[:order].present?
         raise "You can't specify a limit, it's forced to be the batch_size"  if options[:limit].present?
@@ -77,4 +81,4 @@ def batch_order
       "#{@klass.table_name}.#{@klass.primary_key} ASC"
     end
   end
-end
+end

activerecord/test/cases/batches_test.rb

@@ -8,7 +8,7 @@ def setup
     @posts = Post.order("id asc")
     @total = Post.count
   end
-  
+
   def test_each_should_excecute_one_query_per_batch
     assert_queries(Post.count + 1) do
       Post.find_each(:batch_size => 1) do |post|
@@ -28,7 +28,17 @@ def test_each_should_raise_if_the_limit_is_set
       Post.find_each(:limit => 1) { |post| post }
     end
   end
-
+
+  def test_warn_if_limit_scope_is_set
+    ActiveRecord::Base.logger.expects(:warn)
+    Post.limit(1).find_each { |post| post }
+  end
+
+  def test_warn_if_order_scope_is_set
+    ActiveRecord::Base.logger.expects(:warn)
+    Post.order("title").find_each { |post| post }
+  end
+
   def test_find_in_batches_should_return_batches
     assert_queries(Post.count + 1) do
       Post.find_in_batches(:batch_size => 1) do |batch|
@@ -58,4 +68,4 @@ def test_find_in_batches_shouldnt_excute_query_unless_needed
       Post.find_in_batches(:batch_size => post_count + 1) {|batch| assert_kind_of Array, batch }
     end
   end
-end
+end