Refactoring

  1. Create a branch called refactoring
  2. Take a look into the solution for the exercise on Debugging1 below.
  3. Create a file refactoring.md with the answer the following questions:
    • What code smells do you identify?
    • How would you refactor the script? Describe generally.
    • What must be done before refactoring?
  4. Add and commit your changes
  5. Push your branch to your Git repo and create a merge request
  6. Request a review from one of the lecturers
import logging
from sys import argv, exit

logger = logging.getLogger(__name__)


def kinetic_energy(mass, velocity):
    return 0.5 * mass * velocity**2


def total_energy(samples):
    total = 0
    for mass, velocity in samples:
        ke = kinetic_energy(mass, velocity)
        logger.debug("1/2 * %s * %s ** 2 = %s", mass, velocity, ke)
        total += ke

    return total


def parse_units(input_str: str) -> tuple[float, str]:
    """Splits units from the end of string, returns truncated input and parsed unit"""
    logger.debug("Parsing %s", input_str)
    input_str = input_str.lower().replace(" ", "").replace("\t", "")
    value, unit = None, None
    for unit in (
        "kg",
        "g",
        "km/s",
        "m/s",
        "km/h",
        "feet/s",
    ):
        if input_str.endswith(unit):
            value = input_str.replace(unit, "")
            break

    logger.debug("Parsed value '%s' and unit '%s'", value, unit)
    return float(value), unit


def convert_units(value, unit):
    if unit == "g":
        return value / 1000
    elif unit == "kg":
        return value
    elif unit == "km/h":
        return value * 1000 / (60**2)
    elif unit == "m/s":
        return value
    elif unit == "feet/s":
        return value * 0.3048
    raise ValueError("Unsupported unit type: %s", unit)


def read_data(file_path):
    samples = []

    with open(file_path, "r") as f:
        for line in f:
            try:
                parts = line.strip().split("@")
                mass_value, unit = parse_units(parts[0])
                mass = convert_units(mass_value, unit)
                logger.info("Conversion Mass %s %s to %s Kg", mass_value, unit, mass)

                velocity_value, unit = parse_units(parts[1])
                velocity = convert_units(velocity_value, unit)
                logger.info(
                    "Conversion Velocity %s %s to %s m/s",
                    velocity_value,
                    unit,
                    velocity,
                )
                samples.append((mass, velocity))
            except Exception:
                logger.error("Failed processing %s ", line.strip())
                continue

    return samples


if __name__ == "__main__":
    logging.basicConfig()
    if len(argv) < 2:
        logging.critical("Usage: %s filename [--debug]", argv[0])
        exit(1)
    if "--debug" in argv[1:]:
        logger.setLevel(logging.DEBUG)
    filename = argv[1]
    data = read_data(filename)
    print("Total energy:", total_energy(data), "J")