diff options
| -rw-r--r-- | finance/income.py | 26 | ||||
| -rw-r--r-- | finance/test_income.py | 13 |
2 files changed, 36 insertions, 3 deletions
diff --git a/finance/income.py b/finance/income.py index 12d5d4e..94759ff 100644 --- a/finance/income.py +++ b/finance/income.py @@ -1,10 +1,32 @@ import dataclasses +from datetime import datetime @dataclasses.dataclass(kw_only=True, frozen=True) class Income: + """Income models financial income paid on the first day of a month""" amount: float - def integrate(self, delta_t: int) -> float: - return delta_t * self.amount + def integrate(self, start: datetime, end: datetime) -> float: + """Integrate the income from a start to an end date""" + + retval = 0.0 + + current = datetime(start.year, start.month, 1) + + if start == current: + retval += self.amount + + while True: + if current.month == 12: + current = datetime(current.year + 1, 1, 1) + else: + current = datetime(current.year, current.month + 1, 1) + + if current <= end: + retval += self.amount + else: + break + + return retval diff --git a/finance/test_income.py b/finance/test_income.py index 21d42f7..0ce3507 100644 --- a/finance/test_income.py +++ b/finance/test_income.py @@ -1,6 +1,17 @@ +from datetime import datetime + from finance import income def test_income_integration() -> None: inc = income.Income(amount=3000.0) - assert inc.integrate(5) == 15000.0 + + tests = ( + (datetime(2024, 3, 12), datetime(2024, 4, 2), 3000.0), + (datetime(2024, 3, 1), datetime(2024, 3, 15), 3000.0), + (datetime(2024, 2, 25), datetime(2024, 3, 1), 3000.0), + (datetime(2024, 2, 25), datetime(2024, 6, 12), 12000.0), + ) + + for test in tests: + assert inc.integrate(start=test[0], end=test[1]) == test[2] |