How to mimic a dictionary for unit testing with pytest

Question

I want to test the following function using pytest:

def validate_account(number):
    try:
    
        number = int(number)
    
    except:
    
        raise ValueError("Please enter a valid account number")
    
    if int(number) not in accounts_dict:
    
        raise Exception("Pleaseeee enter a valid account number.")
    
    return number

accounts_dict gets items added later on. For unit testing with pytest, how can I mimic this dictionary to test per whether or not a number is in dictionary?

As of now, accounts_dict is empty. And, when I try to assert validate_account("1") == 1, it's throwing the 'Pleaseeee' exception (not in accounts_dict dictionary). I have googled and tried few different options like accounts_dict = Mock(return_value =n), accounts_dict.get('1') != None etc., but they are not helping. Help will be much appreciated.

Answer 1

If the dict is an argument (as it should) you can do this

def validate_account(number, accounts_dict):
...

def test_validate_account__valid():
    assert validate_account("1", {1:True}) == 1

def test_validate_account__invalid():
    with pytest.raises(Exception):
        validate_account("1", {2:True})