text: import datetime
  
  import rdflib
  from rdflib.plugins.sparql import operators
  from rdflib.plugins.sparql import sparql
  import pytest
  
  def test_date_cast():
      now = datetime.datetime.now()
      today = now.date()
  
      literal = rdflib.Literal(now)
      result = operators.date(literal)
      assert isinstance(result, datetime.date)
      assert result == today
  
      literal = rdflib.Literal(today)
      result = operators.date(literal)
      assert isinstance(result, datetime.date)
      assert result == today
  
  
  def test_datetime_cast():
      now = datetime.datetime.now()
      literal = rdflib.Literal(now)
      result = operators.datetime(literal)
      assert isinstance(result, datetime.datetime)
      assert result == now
  
  
  def test_datetime_cast_type_error():
      literal = rdflib.Literal("2020-01-02")
      with pytest.raises(sparql.SPARQLError):
          operators.date(literal)
  