def test_can_parse_currency_exchange_line_with_shortcuts(self):
amount, from_, to = parse_exchange_line('$10 to CAD')
self.assertEqual(10, amount)
self.assertEqual('USD', from_)
self.assertEqual('CAD', to)
amount, from_, to = parse_exchange_line('10 CAD to $')
self.assertEqual(10, amount)
self.assertEqual('CAD', from_)
self.assertEqual('USD', to)
def test_raise_error_if_cant_parse_currency_exchange_line(self):
with self.assertRaises(ValueError):
parse_exchange_line('')
with self.assertRaises(ValueError):
parse_exchange_line('USD to')
with self.assertRaises(ValueError):
parse_exchange_line('to USD')
def exchange_currency(message):
format_recommendation = 'Please use format like this: \n/exchange 10 USD to THB.'
chat_id = message['chat']['id']
exchange_message_text = message['text'].lstrip('/exchange').strip()
if not exchange_message_text:
return send_message(chat_id, format_recommendation)
try:
amount, from_, to = parse_exchange_line(exchange_message_text)
except ValueError as ex:
return send_message(chat_id, f'{str(ex)}\n{format_recommendation}')
try:
exchanged_amount = amount * get_exchange_rate(from_, to)
except ValueError as ex:
return send_message(chat_id, f'{str(ex)}')
return send_message(
chat_id, f'{amount:.2f} {from_} ~ {exchanged_amount:.2f} {to}')
def test_can_parse_currency_exchange_line_without_amount(self):
amount, from_, to = parse_exchange_line('USD to CAD')
self.assertEqual(1, amount)
self.assertEqual('USD', from_)
self.assertEqual('CAD', to)
def test_can_parse_currency_exchange_line_register_of_symbols_not_have_meaning(self):
amount, from_, to = parse_exchange_line('10 Usd to cAD')
self.assertEqual(10, amount)
self.assertEqual('USD', from_)
self.assertEqual('CAD', to)
def test_can_parse_currency_exchange_line_without_whitespaces(self):
amount, from_, to = parse_exchange_line('12.7531USDtoCAD')
self.assertEqual('12.7531', str(amount))
self.assertEqual('USD', from_)
self.assertEqual('CAD', to)
def test_can_parse_currency_exchange_line_with_decimal_value(self):
amount, from_, to = parse_exchange_line('12.7531 USD to CAD')
self.assertEqual('12.7531', str(amount))
self.assertEqual('USD', from_)
self.assertEqual('CAD', to)
def test_can_parse_currency_exchange_line_with_full_specified_names(self):
amount, from_, to = parse_exchange_line('10 USD to CAD')
self.assertEqual(10, amount)
self.assertEqual('USD', from_)
self.assertEqual('CAD', to)