def testVirtualFieldSingle(self):

        resource = current.s3db.resource("typeof_hierarchy")
        row = self.rows["HIERARCHY1"]

        # vsfield returns "test"

        expr = FS("vsfield").typeof("test")
        result = expr(resource, row, virtual=True)
        self.assertTrue(result)

        expr = FS("vsfield").typeof("other")
        result = expr(resource, row, virtual=True)
        self.assertFalse(result)

        expr = FS("vsfield").typeof(["test", "test1", "test2"])
        result = expr(resource, row, virtual=True)
        self.assertTrue(result)

        expr = FS("vsfield").typeof(["other", "other1", "other2"])
        result = expr(resource, row, virtual=True)
        self.assertFalse(result)

    # -------------------------------------------------------------------------
Returns the property value of a variant in the correct ordering of the
dataset/ETHPy150Open sahana/eden/modules/unit_tests/s3/s3hierarchy.py/S3TypeOfTests.testVirtualFieldSingle--crossover with--dataset/ETHPy150Open diefenbach/django-lfs/lfs/catalog/models.py/Product.get_variant_properties_for_parent