rounder.py

import decimal as d
from typing import Dict


def round_costs(cost_datum: Dict[str, object]) -> Dict[str, object]:
    cd_copy = {}
    for key, value in cost_datum.items():
        if isinstance(value, float):
            quantized = d.Decimal(value).quantize(
                d.Decimal("0.01"), rounding=d.ROUND_05UP
            )
            cd_copy[key] = float(quantized)
        else:
            cd_copy[key] = value
    return cd_copy


def test_rounder():
    cd = {
        "one": 3.14242525,
        "two": "bad",
        "three": 1,
        "four": 9.7583,
        "five": 1.0,
        "six": 8.7349,
    }
    res = round_costs(cd)
    assert res["one"] == 3.14
    assert res["two"] == "bad"
    assert res["three"] == 1
    assert res["four"] == 9.76
    assert res["five"] == 1.0
    assert res["six"] == 8.73

def test_with_example():
    example = {
        "total_cost": 500,
        "coinsurance": 0,
        "code": "82805",
        "net_cost": 424.919999999999999,
        "deductable_remaining": {
            "IND": 1.7976931348623157e308,
            "FAM": 1.7976931348623157e308,
        },
    }

    res = round_costs(example)
    assert res["net_cost"] == 424.92