corrected AR find_each and find_in_batches to raise when the user uses select but does not specify the primary key

Signed-off-by: José Valim <jose.valim@gmail.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/activerecord/test/cases/batches_test.rb b/activerecord/test/cases/batches_test.rb
index 83deabb5b7..dcc49e12ca 100644
--- a/activerecord/test/cases/batches_test.rb
+++ b/activerecord/test/cases/batches_test.rb
@@ -17,6 +17,20 @@ class EachTest < ActiveRecord::TestCase
     end
   end
 
+  def test_each_should_raise_if_select_is_set_without_id
+    assert_raise(RuntimeError) do
+      Post.find_each(:select => :title, :batch_size => 1) { |post| post }
+    end
+  end
+
+  def test_each_should_execute_if_id_is_in_select
+    assert_queries(4) do
+      Post.find_each(:select => "id, title, type", :batch_size => 2) do |post|
+        assert_kind_of Post, post
+      end
+    end
+  end
+
   def test_each_should_raise_if_the_order_is_set
     assert_raise(RuntimeError) do
       Post.find_each(:order => "title") { |post| post }