#632·Bogus

CodiceFiscale generator is not deterministic

Author: MephistofelesCreated Mar 17, 2026Updated Mar 17, 2026

Bogus NuGet Package

35.6.5

.NET Version

.NET 10

Visual Studio Version

No response

What operating system are you using?

Windows

What locale are you using with Bogus?

it

Problem Description

Given a static seed CodiceFiscale should generate a deterministic code, like other generators, but it doesn't. It depends on GetHashCode(), which itself is not deterministic.

LINQPad Example or Reproduction Steps

csharp
public sealed class Player
{
    public required Guid Id { get; set; }
    public required string FirstName { get; set; }
    public required string LastName { get; set; }
    public required string TaxCode { get; set; }
}

Randomizer.Seed = new Random(9612867);

var testPlayers = new Faker<Player>("it")
    .StrictMode(true)
    .RuleFor(x => x.Id, f => f.Random.Guid())
    .RuleFor(x => x.FirstName, f => f.Name.FirstName())
    .RuleFor(x => x.LastName, f => f.Name.LastName())
    .RuleFor(x => x.TaxCode, f => f.Person.CodiceFiscale());

var players = testPlayers.Generate(2);

Expected Behavior

Every time I run the test using this code it should produce the exact same codes.

Actual Behavior

Every run Bogus generates a different codes.

Known Workarounds

No response

Could you help with a pull-request?

Yes