Merge pull request #11896 from nkondratyev/fix_pg_columns_for_distinct

Fixed #columns_for_distinct of postgresql adapter

Conflicts:
	activerecord/CHANGELOG.md

1 files changed, 11 insertions, 0 deletions

diff --git a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
index 960e33b329..aaa874af7d 100644
--- a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
@@ -355,6 +355,17 @@ module ActiveRecord
         assert_equal "posts.title, posts.updater_id AS alias_0", @connection.columns_for_distinct("posts.title", ["posts.updater_id desc nulls last"])
       end
 
+      def test_columns_for_distinct_without_order_specifiers
+        assert_equal "posts.title, posts.updater_id AS alias_0",
+          @connection.columns_for_distinct("posts.title", ["posts.updater_id"])
+
+        assert_equal "posts.title, posts.updater_id AS alias_0",
+          @connection.columns_for_distinct("posts.title", ["posts.updater_id nulls last"])
+
+        assert_equal "posts.title, posts.updater_id AS alias_0",
+          @connection.columns_for_distinct("posts.title", ["posts.updater_id nulls first"])
+      end
+
       def test_raise_error_when_cannot_translate_exception
         assert_raise TypeError do
           @connection.send(:log, nil) { @connection.execute(nil) }