ClosestTo utility class

closest_to.py

from datetime import datetime, timedelta

DEFAULT_EPSILON = {
    datetime: timedelta(seconds=5),
}


class ClosestTo:
    """Utility class to check value is closest to other"""

    def __init__(self, origin_value, epsilon=None):
        self.epsilon = epsilon or DEFAULT_EPSILON[type(origin_value)]
        self.value = origin_value

    def __eq__(self, other):
        """Perform check"""
        if other is None:
            return False
        # difference in  +epsilon to -epsilon range
        return self.epsilon > (self.value - other) > -self.epsilon

    def __repr__(self):
        """Representation"""
        return f"ClosestTo({repr(self.value)}, epsilon={repr(self.epsilon)})"

# ==== EXAMPLE USAGE ====
def some_func():
    ... # some process
    result['dt'] = datetime.now() 
    return result

def test_some_func():
    result = some_func()
    ...
    assert result['dt'] == ClosestTo(datetime.now())