test_assets.py 文件源码

def test_lookup_symbol(self):

        # Incrementing by two so that start and end dates for each
        # generated Asset don't overlap (each Asset's end_date is the
        # day after its start date.)
        dates = pd.date_range('2013-01-01', freq='2D', periods=5, tz='UTC')
        df = pd.DataFrame.from_records(
            [
                {
                    'sid': i,
                    'symbol':  'existing',
                    'start_date': date.value,
                    'end_date': (date + timedelta(days=1)).value,
                    'exchange': 'NYSE',
                }
                for i, date in enumerate(dates)
            ]
        )
        self.env.write_data(equities_df=df)
        finder = self.asset_finder_type(self.env.engine)
        for _ in range(2):  # Run checks twice to test for caching bugs.
            with self.assertRaises(SymbolNotFound):
                finder.lookup_symbol('NON_EXISTING', dates[0])

            with self.assertRaises(MultipleSymbolsFound):
                finder.lookup_symbol('EXISTING', None)

            for i, date in enumerate(dates):
                # Verify that we correctly resolve multiple symbols using
                # the supplied date
                result = finder.lookup_symbol('EXISTING', date)
                self.assertEqual(result.symbol, 'EXISTING')
                self.assertEqual(result.sid, i)