old_contents: from django.test import SimpleTestCase
  from jsonobject.exceptions import BadValueError
  
  from corehq.apps.userreports.reports.specs import ReportColumn
  
  
  class TestReportColumn(SimpleTestCase):
      def testBadAggregation(self):
          with self.assertRaises(BadValueError):
              ReportColumn.wrap({
                  "aggregation": "simple_",
                  "field": "doc_id",
                  "type": "field",
              })
  
      def testGoodFormat(self):
          for format in [
              'default',
              'percent_of_total',
          ]:
              self.assertEquals(ReportColumn, type(
                  ReportColumn.wrap({
                      "aggregation": "simple",
                      "field": "doc_id",
                      "format": format,
                      "type": "field",
                  })
              ))
  
      def testBadFormat(self):
          with self.assertRaises(BadValueError):
              ReportColumn.wrap({
                  "aggregation": "simple",
                  "field": "doc_id",
                  "format": "default_",
                  "type": "field",
              })
  
new_contents: from django.test import SimpleTestCase
  from jsonobject.exceptions import BadValueError
  from sqlagg import SumWhen
  from corehq.apps.userreports.sql import _expand_column
  
  from corehq.apps.userreports.reports.specs import ReportColumn
  
  
  class TestReportColumn(SimpleTestCase):
      def testBadAggregation(self):
          with self.assertRaises(BadValueError):
              ReportColumn.wrap({
                  "aggregation": "simple_",
                  "field": "doc_id",
                  "type": "field",
              })
  
      def testGoodFormat(self):
          for format in [
              'default',
              'percent_of_total',
          ]:
              self.assertEquals(ReportColumn, type(
                  ReportColumn.wrap({
                      "aggregation": "simple",
                      "field": "doc_id",
                      "format": format,
                      "type": "field",
                  })
              ))
  
      def testBadFormat(self):
          with self.assertRaises(BadValueError):
              ReportColumn.wrap({
                  "aggregation": "simple",
                  "field": "doc_id",
                  "format": "default_",
                  "type": "field",
              })
  
  
  class TestExpandReportColumn(SimpleTestCase):
  
      def test_expansion(self):
          column = ReportColumn(
              type="field",
              field="lab_result",
              display="Lab Result",
              format="default",
              aggregation="expand",
              description="foo"
          )
          cols = _expand_column(column, ["positive", "negative"])
  
          self.assertEqual(len(cols), 2)
          self.assertEqual(type(cols[0].view), SumWhen)
          self.assertEqual(cols[1].view.whens, {'negative':1})
  
subject: Add simple test for column expansion