text: # Copyright DataStax, Inc.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  # http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  import unittest
  
  from cassandra.cqlengine.columns import Column, Set, List, Text
  from cassandra.cqlengine.operators import *
  from cassandra.cqlengine.statements import (UpdateStatement, WhereClause,
                                    AssignmentClause, SetUpdateClause,
                                    ListUpdateClause)
  import six
  
  
  class UpdateStatementTests(unittest.TestCase):
  
      def test_table_rendering(self):
          """ tests that fields are properly added to the select statement """
          us = UpdateStatement('table')
          self.assertTrue(six.text_type(us).startswith('UPDATE table SET'), six.text_type(us))
          self.assertTrue(str(us).startswith('UPDATE table SET'), str(us))
  
      def test_rendering(self):
          us = UpdateStatement('table')
          us.add_assignment(Column(db_field='a'), 'b')
          us.add_assignment(Column(db_field='c'), 'd')
          us.add_where(Column(db_field='a'), EqualsOperator(), 'x')
          self.assertEqual(six.text_type(us), 'UPDATE table SET "a" = %(0)s, "c" = %(1)s WHERE "a" = %(2)s', six.text_type(us))
  
          us.add_where(Column(db_field='a'), NotEqualsOperator(), 'y')
          self.assertEqual(six.text_type(us), 'UPDATE table SET "a" = %(0)s, "c" = %(1)s WHERE "a" = %(2)s AND "a" != %(3)s', six.text_type(us))
  
      def test_context(self):
          us = UpdateStatement('table')
          us.add_assignment(Column(db_field='a'), 'b')
          us.add_assignment(Column(db_field='c'), 'd')
          us.add_where(Column(db_field='a'), EqualsOperator(), 'x')
          self.assertEqual(us.get_context(), {'0': 'b', '1': 'd', '2': 'x'})
  
      def test_context_update(self):
          us = UpdateStatement('table')
          us.add_assignment(Column(db_field='a'), 'b')
          us.add_assignment(Column(db_field='c'), 'd')
          us.add_where(Column(db_field='a'), EqualsOperator(), 'x')
          us.update_context_id(3)
          self.assertEqual(six.text_type(us), 'UPDATE table SET "a" = %(4)s, "c" = %(5)s WHERE "a" = %(3)s')
          self.assertEqual(us.get_context(), {'4': 'b', '5': 'd', '3': 'x'})
  
      def test_additional_rendering(self):
          us = UpdateStatement('table', ttl=60)
          us.add_assignment(Column(db_field='a'), 'b')
          us.add_where(Column(db_field='a'), EqualsOperator(), 'x')
          self.assertIn('USING TTL 60', six.text_type(us))
  
      def test_update_set_add(self):
          us = UpdateStatement('table')
          us.add_update(Set(Text, db_field='a'), set((1,)), 'add')
          self.assertEqual(six.text_type(us), 'UPDATE table SET "a" = "a" + %(0)s')
  
      def test_update_empty_set_add_does_not_assign(self):
          us = UpdateStatement('table')
          us.add_update(Set(Text, db_field='a'), set(), 'add')
          self.assertFalse(us.assignments)
  
      def test_update_empty_set_removal_does_not_assign(self):
          us = UpdateStatement('table')
          us.add_update(Set(Text, db_field='a'), set(), 'remove')
          self.assertFalse(us.assignments)
  
      def test_update_list_prepend_with_empty_list(self):
          us = UpdateStatement('table')
          us.add_update(List(Text, db_field='a'), [], 'prepend')
          self.assertFalse(us.assignments)
  
      def test_update_list_append_with_empty_list(self):
          us = UpdateStatement('table')
          us.add_update(List(Text, db_field='a'), [], 'append')
          self.assertFalse(us.assignments)
  