def test_should_aggregate_consumption_across_all_appliances():
# given
household = household_with(monthly_appliance_usage=[
appliance_usage_with(appliance=appliance_with(consumption_watts='300'),
daytime_hours='5', nighttime_hours='3'),
appliance_usage_with(appliance=appliance_with(consumption_watts='500'),
daytime_hours='6', nighttime_hours='10')
])
# when
daytime_kwh, nighttime_kwh = household.monthly_kwh
# then
assert daytime_kwh == Decimal('4.5')
assert nighttime_kwh == Decimal('5.9')
def test_should_calculate_kwh_consumption_for_specified_hours_usage():
# given
appliance = appliance_with(consumption_watts=400)
# when
kwh_consumption = appliance.get_kwh_consumed(15)
# then
assert kwh_consumption == Decimal('6')
def test_should_provide_daytime_kwh_consumption_based_on_appliance_power_and_daytime_hours_used(
):
# given
appliance_usage = appliance_usage_with(
appliance=appliance_with(consumption_watts='250'), daytime_hours='50')
# when
daytime_kwh = appliance_usage.daytime_kwh
# then
assert daytime_kwh == Decimal('12.5')
def test_should_provide_nighttime_kwh_consumption_based_on_appliance_power_and_nighttime_hours_used(
):
# given
appliance_usage = appliance_usage_with(
appliance=appliance_with(consumption_watts='250'),
nighttime_hours='10')
# when
nighttime_kwh = appliance_usage.nighttime_kwh
# then
assert nighttime_kwh == Decimal('2.5')
def test_should_calculate_day_and_night_kwh_used_by_specified_appliances_based_on_their_usage_and_power_consumption():
# given
household = household_with(monthly_appliance_usage=[
appliance_usage_with(
appliance=appliance_with(consumption_watts='300'),
daytime_hours='5',
nighttime_hours='3'
)
])
# when
daytime_kwh, nighttime_kwh = household.monthly_kwh
# then
assert daytime_kwh == Decimal('1.5')
assert nighttime_kwh == Decimal('0.9')
def test_should_report_cheapest_tariff_per_household():
# given
tariff_1 = tariff_with(name='Tariff 1', standing_charge_pounds='6.00', day_unit_cost_pounds_per_kw='0.135',
night_unit_cost_pounds_per_kw='0.135')
tariff_2 = tariff_with(name='Tariff 2', standing_charge_pounds='6.30', day_unit_cost_pounds_per_kw='0.150',
night_unit_cost_pounds_per_kw='0.120')
tariff_3 = tariff_with(name='Tariff 3', standing_charge_pounds='6.00', day_unit_cost_pounds_per_kw='0.160',
night_unit_cost_pounds_per_kw='0.110')
tariff_4 = tariff_with(name='Tariff 4', standing_charge_pounds='6.15', day_unit_cost_pounds_per_kw='0.150',
night_unit_cost_pounds_per_kw='0.130')
tariff_source = MagicMock()
tariff_source.get_tariffs = MagicMock(return_value=[tariff_1, tariff_2, tariff_3, tariff_4])
display = MagicMock()
tariff_calculator = CheapestTariffReportService(tariff_source=tariff_source, display=display)
first_household = household_with(
monthly_appliance_usage=[
appliance_usage_with(
appliance=appliance_with(consumption_watts='500'),
daytime_hours='12',
nighttime_hours='8'
),
appliance_usage_with(
appliance=appliance_with(consumption_watts='2500'),
daytime_hours='12',
nighttime_hours='8'
),
appliance_usage_with(
appliance=appliance_with(consumption_watts='70'),
daytime_hours='16',
nighttime_hours='60'
),
appliance_usage_with(
appliance=appliance_with(consumption_watts='2100'),
daytime_hours='1',
nighttime_hours='1'
)
]
)
second_household = household_with(
monthly_appliance_usage=[
appliance_usage_with(
appliance=appliance_with(consumption_watts='500'),
daytime_hours='0',
nighttime_hours='12'
),
appliance_usage_with(
appliance=appliance_with(consumption_watts='2500'),
daytime_hours='0',
nighttime_hours='8'
),
appliance_usage_with(
appliance=appliance_with(consumption_watts='70'),
daytime_hours='12',
nighttime_hours='48'
),
appliance_usage_with(
appliance=appliance_with(consumption_watts='2100'),
daytime_hours='1',
nighttime_hours='2'
)
]
)
household_source = MagicMock()
household_source.get_households = MagicMock(return_value=[first_household, second_household])
# when
tariff_calculator.generate_report_for_households_in(household_source)
# then
display.render_results.assert_called_once()
args, kwargs = display.render_results.call_args
results = args[0]
assert len(results) == 2
first_result = results[0]
assert first_result.household == first_household
assert first_result.cheapest_tariff == tariff_1
assert first_result.monthly_cost_pounds == Decimal('15.38520')
second_result = results[1]
assert second_result.household == second_household
assert second_result.cheapest_tariff == tariff_3
assert second_result.monthly_cost_pounds == Decimal('10.16200')